Band Walk Alert Tenkyo — System Trade Edition User Manual

Chapter 1:What Is the System Trade Edition?

1-1. Core Concept

Band Walk Alert Tenkyo is a logic that focuses on the “initial velocity of price” during a Bollinger Band expansion. It thoroughly eliminates gambling-style counter-trend calls that try to predict tops and bottoms, and detects a move as an “initial thrust” only at the moment momentum is statistically confirmed. Rather than chasing a gambler’s jackpot, the system prioritizes “not losing” above all else — the moment it judges a trend has stopped extending, it withdraws from the market early, protecting capital until the next “big wave” arrives.

Band Walk Alert Tenkyo System Trade is the edition that wires this detection logic directly into automatic order entry and automatic exit on an MT4 account. The statistical calculation behind signal detection is exactly the same as the sister indicator-only product, “Band Walk Alert Tenkyo” — the moment a signal lights up on the chart, it also places or closes the order.

There are two main differences from the indicator-only edition (display only):

The signals that appear on the chart (ENTRY / OW1–4 / SEC / FAIL, etc.) drive real orders (new entries and exits), not just a visual display.
An “Auto-Trading Settings Panel” is added at the bottom right of the screen, giving you control over lot management, a hard stop-loss, a time-of-day filter, maximum spread, a daily loss cap, and an emergency stop — the safety features you need when real money is on the line.

Chapter 2:Installation and Setup

2-1. Getting and Placing the Files

Download the file. What you receive is a ZIP archive.
Right-click the ZIP file and choose “Extract All” (or “Unzip”) to pull out the BandWalkAlertTENKYO_sys.ex4 file.
From the MT4 menu, click “File” > “Open Data Folder,” then open “MQL4” > “Experts” inside the folder that opens.
Copy (paste) the extracted BandWalkAlertTENKYO_sys.ex4 file into this folder.
Copy every bundled recommended-parameter settings file into the “MQL4” > “Files” folder.
In the “Navigator” panel on the left side of MT4 (press Ctrl + N if it isn’t visible), right-click “Expert Advisors” and choose “Refresh” — the EA’s name will then appear in the list.
Double-click the EA that appears in the list, or grab it with the mouse and drag it onto the chart you want to run it on.

2-2. Actually Enabling Auto-Trading (Additional Step Required for the System Trade Edition)

Everything above is shared with the display-only indicator edition. Because the System Trade Edition places real orders, the following additional settings are required.

Turn the “AutoTrading” button ON in the MT4 top toolbar (it switches from orange to green). Orders will not execute while it’s off.
On the EA’s properties screen (the “Common” tab), check “Allow live trading.” If this is left unchecked, order placement will fail with error 4109, “AutoTrading is not allowed.”
Under “Tools” > “Options” > the “Expert Advisors” tab, add https://tenkyo-fx.com to the WebRequest allow list.
Immediately after attaching the EA to a chart, no real orders will be placed at all until you click “I understand and accept full responsibility” in the Auto-Trading Settings Panel at the bottom right of the screen (see Chapter 5). If you forget this step, signals will light up on the chart but no orders will actually go through — please be careful.

Chapter 3:Filling In History Data (Critical: Data Integrity)

For the dashboard’s performance tally and session judgment to work correctly, MT4 needs to be properly loaded with the historical price data that the statistical calculations are based on. Skipping this step will make the dashboard’s numbers meaningless, so be sure to carry it out.

Open the History Center: press the F2 key.
Drill into the currency pair’s hierarchy: click the “+” mark next to the pair you want to trade (e.g., Forex > USDJPY) to expand it.
Enable the timeframe you want to fetch: find the timeframe you’re trading in the list (e.g., “M15”) and look at the icon just to its left. If the icon is gray, double-click quickly on the timeframe’s text. Once the icon turns colored (yellow and green), it has been enabled successfully.
Download: click the “Download” button at the bottom, and click “OK” through any warning that appears. Wait until the green bar reaches the right edge.
Restart MT4: once it’s done, close MT4 entirely and relaunch it.
Run the forced scroll: after restarting, click the Environment Settings tab at the top-left of the chart, then click “Fetch Past Bars” inside the panel. The chart will automatically fast-scroll into the past to fill in any missing data. Wait until the screen stops moving.

Chapter 4:Signals, Entry, and Exit Logic (A Signal Is an Order)

Each label that lights up on the chart is the result of a calculation correlating the dynamic change of the Bollinger Bands with the candlesticks. This detection logic itself is identical to the indicator edition, but in the System Trade Edition a lit signal drives an actual order (entry or exit) directly.

4-1. The Entry Process (From Warning Sign to Confirmation)

EXPANSION (warning sign): fires the instant the width of the Bollinger Bands’ third standard deviation (±3σ) expands beyond a specified “band expansion speed (TH)” compared with the previous bar. It’s an alert that the statistical “soil” for a trend to develop has been prepared.
ENTRY (LONG / SHORT): once every condition is cleared after EXPANSION fires, an arrow and price are displayed and, at the same instant, a new market order is placed (OrderSend). When Scramble Mode is set to aggressive, an ENTRY signal can appear suddenly without EXPANSION ever lighting up.

4-2. Exit Logic (OW1–4: Four Definitions of a Trend’s End)

The reasoning for “the band walk is over” is classified into four categories, in order to maximize profit while capping risk. All four close the position at market the instant they fire.

OW1 Convergence: closes the instant the Bollinger Band expansion stalls and the band width turns to contraction (a squeeze). This is the most standard exit, signaling that the trend’s momentum has died.
OW2 Reversal: closes when a specified number of consecutive candles form against the direction of the trade after entry (the “allowed reversal-candle count”).
OW3 Deviation: fires when price falls significantly outside the Bollinger Bands’ second standard deviation (±2σ), judged to have deviated from the trend’s trajectory.
OW4 Center line: closes when price returns to the band’s center line (the Basis). This is the last line of defense as the trend fully collapses and heads toward a range or a reversal.

4-3. Special Exits and Protective Signals

SECURED Small-profit exit: once unrealized profit reaches the “breakeven (BE) move” line and price then pulls back, the position is closed at market at entry price + spread + a specified number of pips (SEC), locking in a small profit. This is defensive logic designed to eliminate outright losses.
FAIL False-break avoidance: an emergency stop-loss signal that closes the position at market immediately — while the damage is still shallow — if, within the first one or two candles after entry, the candle body is pushed back by half or more, indicating the breakout was likely a “lie.”
Mushy Zone: an uncolored region on the chart. This is a “zero-edge” stagnation zone where the bands are not expanding and price is drifting near the center line; all entry logic is automatically shut down inside this zone (no new orders are placed either).

4-4. How Signals Map to Actual Orders

Signal on the Chart	What Actually Happens
ENTRY LONG/SHORT	Places a new market order (OrderSend).
OW1–OW4	Closes the position at market.
SECURED	Closes the position at market (small-profit exit).
FAIL	Closes the position at market (emergency stop-loss to avoid a false break).
SL / TSL	Fills at the same price level as the real stop-loss placed with the broker (see “Hard Stop-Loss” in Chapter 5), at the same time the exit logic makes its determination.

★Order entry and exit only execute on the real-time latest bar (on the first tick right after the determination, on a closed-bar basis) — they are never triggered by recalculation of past bars or by the history scan that happens when you reopen a chart. Strategy Tester runs use the same logic to place simulated orders, so backtesting is possible before going live.

Chapter 5:Auto-Trading Settings Panel (Most Important)

This panel opens when you click the “Auto-Trading Settings” button at the bottom right of the screen. So that nothing is lost when the chart restarts, settings are auto-saved to a dedicated file per currency pair and timeframe (TNK_UserSettings_[pair]_[timeframe].dat) (the “acceptance of responsibility” setting below is the one exception). Even if you run both AUDJPY-M15 and EURJPY-M15 on the same terminal, each is saved to its own separate file, so you can run different lot sizes, allowed spreads, and so on per chart.

5-1. I Understand and Accept Full Responsibility (ACCEPT)

Until you click this button and it turns green ([Done]), no new real orders will be placed at all (internal flag g_userAcceptedRisk).
The state of this button is not saved to a file. Every time the EA restarts (terminal restart, changing the chart’s timeframe, re-attaching the EA, restarting MT4, etc.) it reverts to the un-accepted state. You must click it again every single time you resume operation.

5-2. Lot Sizing Method

Fixed: always trades at the value entered in the “fixed lot size” field.
% Risk: automatically back-calculates the lot size from your allowed loss percentage of account equity and that trade’s stop-loss width (in pips). The result is rounded to the broker’s minimum lot step (MODE_LOTSTEP) and kept within the broker’s minimum/maximum lot range.

Note that this is the opposite way of thinking from a fixed lot. With a fixed lot, you decide the lot size first and the resulting loss amount follows from that; with % Risk, you decide the loss amount (as a %) you’re willing to accept first, and the lot size is back-calculated from it. The formula is as follows:

Loss tolerance = Account equity x Risk %
SL distance    = |Entry price - Stop-loss price| (varies trade by trade, based on the stop-loss width configured for that session)
Lot size       = Loss tolerance / (SL distance x Contract size)

Example: with account equity of $5,000, a risk setting of 1%, an SL distance of 20 pips on this trade (0.0020 for a 4-decimal pair), and a contract size of 100,000 units, the loss tolerance is $50, and the lot size is 50 / (0.0020 x 100,000) = 0.25 lots. If this lot hits the SL, the loss comes out to exactly $50 (1% of equity).

Because the distance to the SL changes trade by trade depending on the stop-loss width configured for that session, the same “% Risk” setting will automatically size the lot larger when the SL is close and smaller when the SL is far, every time. With a fixed lot, the lot size stays the same regardless of how the SL distance changes, so the real risk (loss amount) per trade will vary.
The calculation is based on the account’s current equity, including floating profit and loss — not the balance fixed at the time of deposit. If floating or realized losses reduce equity, the next lot size will automatically shrink as well.
The calculated result is always rounded down to the broker’s minimum lot step, so the actual loss amount will never exceed the configured percentage (it may come in under it).

5-3. Slippage

The allowed slippage (in points) used for both new-entry and exit orders.

5-4. Hard Stop-Loss (Default: ON)

When ON, immediately after a new order fills, the EA places the virtual stop-loss price it manages internally as a real SL on the broker’s server as well (OrderModify). This means that even in an unforeseen event — your PC freezing, MT4 crashing, your internet connection dropping — the broker-side SL still caps your worst-case loss. Because this is the safer setting, we recommend leaving it ON unless you have a specific reason to turn it off.

5-5. Time-of-Day Filter (Bans 1–3)

The time windows configured here (in local time, based on MT4’s TimeLocal()) block new entries only. Setting a start time later than the end time (e.g., 22:00–03:00) makes it work as a window that spans midnight.

★ Important: Signals (such as ENTRY) still light up on the chart during a banned window, and the EA’s internal virtual position state continues to progress normally — only the real order placement is blocked. This means that, for exactly as many signals as fire during a banned window, you’ll see a signal appear with no order actually placed. Additionally, because the EA internally treats itself as holding a virtual position, the next signal won’t fire until that virtual position is closed — meaning you can miss one opportunity as a result. Please be aware of this as a design characteristic before using the filter.

Closing an existing position (OW determination, SL, SEC, etc.) still executes normally during a banned window. Only new entries are blocked.

5-6. Maximum Spread

When ON, if the spread (Ask − Bid) just before an order would be placed exceeds the configured value, that entry is skipped for the round. This guards against buying at a spike price during a sudden spread widening, such as right after a news release.

5-7. Daily Loss Cap

When ON, once that day’s (based on the server date) total realized P&L (closed profit/loss plus swap plus commission) falls to or below the configured amount (in account currency), all further new entries for that day are stopped.

★ Note: This daily realized-P&L tally (g_dailyRealizedPL) resets to 0 on restart. The ON/OFF setting and the cap amount itself are saved to a file, but the counter for “how much have I lost today” is not. If you restart the terminal or the EA during the same day, that day’s tally resets, and trades that should have been blocked by the cap become possible again — please be careful.

5-8. Emergency Stop

Pressing the red button immediately closes all positions at market held by this EA (same currency pair, same magic number) and stops any further new orders. Pressing it again releases the stop and resumes trading. This state is saved to a file, so the emergency-stop state persists across a restart.

5-9. [Extremely Important] Priority Between Input Parameters and Panel Settings

The EA’s “Inputs” screen contains Inp_LotSize, Inp_Slippage, Use_TimeFilter, and Inp_Ban_Time1–3. These are only used as initial values for the Auto-Trading Settings Panel the very first time the EA is attached to that chart (when that chart’s dedicated settings file does not yet exist).

Once a settings file has been created even once (TNK_UserSettings_[symbol]_[timeframe number].dat — the symbol is used exactly as the broker reports it, suffix included, and the timeframe becomes a minute-based number such as 15 for M15; for example, AUDJPY-cd on M15 becomes TNK_UserSettings_AUDJPY-cd_15.dat), changing the Inputs values will no longer have any effect on the EA’s behavior. To change the lot size, slippage, or time filter, always operate the Auto-Trading Settings Panel at the bottom right of the screen directly.

“I changed the Inputs but nothing happened” is the single most likely support question. If you want to reset your configuration back to its initial state, delete the corresponding TNK_UserSettings_[symbol]_[timeframe number].dat file from the MQL4 > Files folder and then restart the EA.

★ This file is saved separately for every combination of currency pair and timeframe. Even running AUDJPY-M15 and EURJPY-M15 at the same time on one terminal, each keeps its own independent configuration (lot size, allowed spread, time filter, etc.), and changing settings on one chart has no effect on the other.

Chapter 6:Environment Settings Panel

This expands when you click the “Environment Settings” toggle button at the top of the chart. It’s a dedicated section for customizing display settings and the environment that the calculations are based on.

Spread Used for Virtual Trades

This setting lines up the virtual-trade performance shown on the dashboard (profit factor, pips gained, etc.) with the reality of the broker you’re using. You can set a spread individually (in pips) for the 8 major currency pairs — EURUSD, USDJPY, and so on — plus a catch-all OTHER for everything else. Type a number directly into the white input box, or fine-tune it with the [-] / [+] buttons beside it (press-and-hold supported). The current chart’s currency pair is highlighted in lime green.

Other Customization

Background color: [Dark] / [Light] — optimizes the color palette of the panels and signals (arrows and text) to match your chart’s background color.
Language: [English] / [Japanese] — instantly switches all text within the panels, as well as the language used for notifications (alerts).
Onion Zone shading: [OFF] / [Light] / [Dark] — chooses whether to highlight the high-edge “Onion Zone” (the band-expansion period) with colored shading on the chart.

External Communication and Data Management (Action Buttons)

Fetch Past Bars: opens a dedicated download dialog (a bar-count selection screen) when clicked. It forcibly loads any missing history data so that past performance can be calculated accurately (see Chapter 3).
Save Settings: writes the spread, theme, language, and other settings you changed in the panel to a local file.

Chapter 7:If You Want to Customize the Logic Parameters (Using a User Settings File)

The System Trade Edition does not include a panel — like the “Parameter Panel” found in the indicator edition — for adjusting the numbers behind the signal-detection logic itself on screen, such as the BB period, entry sensitivity, or stop-loss width. It’s built on the premise that you’ll run it with the bundled or downloaded recommended parameters as-is.

7-1. The System Trade Edition Alone Cannot Create a User Settings File

The System Trade Edition on its own cannot create a user settings file. If you want your own strategy reflected in the auto-trading logic, please obtain the sister indicator product, Band Walk Alert Tenkyo Pro (sold separately).

7-2. How to Load a User Settings File Created in the Indicator Edition

Temporarily attach the sister indicator product, Band Walk Alert Tenkyo Pro, to a chart with the same currency pair and timeframe as the System Trade Edition.
Adjust the numbers in the indicator edition’s Parameter Panel and click “Save Parameters.” This saves TNK_Params_[last 6 characters of the pair]_[timeframe number].csv into the MQL4 > Files folder on the terminal where the indicator edition is running. If you’re running the System Trade Edition on a different terminal, copy this file into that terminal’s MQL4 > Files folder.

★This method simply uses the standard save-file format and load logic exactly as designed. No special file tampering or source-code modification is required.

Chapter 8:Notifications (Push Notifications)

The entry and exit signals that appear on-screen in Band Walk Alert Tenkyo System Trade can be pushed to your phone as notifications.

8-1. Preparation on Your Phone (Finding Your MetaQuotes ID)

Find your MetaQuotes ID, which serves as the “address” push notifications are sent to.

Launch the mobile MT4 app.
Open the settings menu (on iPhone: tap “Settings” at the bottom right; on Android: open the hamburger menu at the top left and choose “Settings”).
Tap “Chats and Messages” (or “Messages”).
Note down or copy the “My MetaQuotes ID: [8-character alphanumeric string]” shown at the bottom of the screen. Note: this ID can change if you reinstall the app, so check it again if notifications stop arriving.

8-2. Configuration on Desktop MT4 (Enabling Notifications)

Launch desktop MT4 and click “Tools” → “Options” in the top menu.
Select the “Notifications” tab.
Check “Enable Push Notifications.”
Enter the 8-character ID you found in 8-1 into the “MetaQuotes ID” field.
Click the “Test” button on the right of the ID field — setup is complete once a “Test Message from [PC name]” notification arrives on your phone.

8-3. Types of Events That Are Notified

Expansion/No Entry: notifies you when the “warning sign” that a band has expanded is detected, or when an entry is skipped because conditions weren’t met.
Entry (LONG/SHORT): notifies you the instant the statistical edge is confirmed and the entry arrow actually lights up. In the System Trade Edition, this is sent at the same moment the actual new-order signal fires.
Exit: notifies you the instant a trade is closed (OW, SL, SEC, FAIL, etc.). In the System Trade Edition, this is sent at the same moment the actual exit signal fires.

★ Note: A notification is purely a notice that “a signal occurred” — it does not indicate whether that round’s order actually succeeded (whether it failed due to insufficient margin, a requote, etc.). The message text does not include that information. If order placement fails, an “Order Failed” panel appears at the bottom right of the chart (see Chapter 11).

Chapter 9:Dashboard and Trade History Panel

9-1. Dashboard (Note: This Is “Virtual Simulation Performance”)

The statistics dashboard shown at the top left of the chart calculates the “full performance of virtual trades” in real time over a specified aggregation period, serving as a monitor for objectively evaluating how effective your settings are. These are numbers calculated by applying the logic, for the specified period, to past data — they are a separate thing from the actual profit and loss this EA has produced through auto-trading.

Display and Function Control via Toggle Buttons

[Dashboard Show/Hide] button: toggles whether the dashboard panel itself is shown or hidden.
[Notifications: ON/OFF] button: the “master switch” for every alert (Chapter 8) the system sends out.

Performance Metrics Explained: nine statistics are displayed, based on the trade results within the aggregation period (shown in silver just below the title).

Metric	Description
Total Trades	The total number of trades made within the specified period. To ensure statistical reliability, treat the numbers with caution unless there’s a sample of at least 100 trades.
Profit Factor	Calculated as “total profit ÷ total loss,” this is the headline metric for evaluating the system. A value of 1.0 means breakeven; 1.5 or higher indicates a logic strong enough to “really compete.” It isn’t meaningful when trade count is low.
Net Profit (Pips)	The final net profit remaining after subtracting total loss pips from total profit pips across all trades. This is calculated as a realistic figure with the “spread” entered in the Environment Settings Panel already deducted.
Max Drawdown	The depth, in pips, of the deepest dip that equity (cumulative pips) falls to after reaching a new high. The smaller this number, the more consistently the equity curve has trended upward.
Drawdown Ratio	Shows what percentage the max drawdown represents relative to the net profit achieved (formula: max drawdown ÷ net profit × 100).
Expectancy (Pips)	The expected value of how many pips of profit (or loss) you can expect, on average, per trade (formula: net profit ÷ total trades).
Wins / Losses	A breakdown of trades that ended in profit (wins) versus trades that ended in a loss (losses).
Avg. Win/Loss	Shows the average pips gained per winning trade side by side with the average pips lost per losing trade — a metric for checking your so-called “risk-reward” balance.

9-2. Trade History Panel (Detailed Verification of Virtual Trades)

This panel expands when you click the “Trade History” toggle button at the top right of the chart. It lists the full history of virtual trades made within the specified backtest period, giving you an analysis tool for verifying “at what point, and for what reason” each trade closed under your configured parameters.

Reading the Trade History List: up to 60 rows (per page) of history data are shown, newest first, laid out in a monospaced font. Text is color-coded between winning and losing trades.

TIME: the date and time the trade was closed
TYPE: LONG (buy) or SHORT (sell)
ENTRY / EXIT: the entry price and exit price
PIPS: the profit/loss in pips for that trade
REASON: the logical basis for why the trade ended (SEC = small-profit exit / SL·TSL = the initial stop-loss or the temporary stop-loss used in Scramble mode / OW1–OW4 = a logical exit that determined the trend had ended / FAL (FAIL) = an exit to avoid a false break caused by a wick or a sharp reversal)

Scrolling and Navigating the List: when there are more than 60 records, four blue sub-buttons at the top of the panel let you page back through past data. [-] scrolls to older history, [+] scrolls to newer history, and pressing the same button again stops the scroll. The [Jump to Latest (TOF)] button returns you to the top of the list (the most recent trade history) in one click.

Exporting a Performance Report to CSV: clicking the green “Export” button generates a CSV file containing all data currently aggregated on the dashboard for that period. The top of the file contains a performance summary (profit factor, net profit, max drawdown, win rate, etc.), followed by the detailed history of every trade (time, direction, price, P&L, exit reason). The file is saved to the “Common” > “Files” folder, with a filename like TNK_Report_USDJPY_15_[timestamp].csv that automatically includes the currency pair and timeframe.

9-3. Your Real Positions and P&L Are Found Elsewhere, Not on the Dashboard

The dashboard and trade history panel above are purely a virtual simulation. Check the “Open Real Positions” panel at the bottom right of the screen for information about the positions you actually hold (entry time, entry price, current floating P&L, etc.). Check the “Account History” tab in MT4 for the official record of your actual trading profit and loss.

Chapter 10:Important Notes for Safe Operation

Managing magic numbers: if you run this EA on multiple timeframes or multiple charts for the same currency pair at the same time, always set a different magic number for each chart. If you open two or more charts with the same currency pair and the same magic number, one chart may misidentify the other’s position as “its own,” which can cause new entries to fail to be blocked correctly, or trigger unintended duplicate exit processing.
The Auto-Trading Settings Panel is independent per currency pair and timeframe: as described in Chapter 5, Section 5-9, lot settings, the time filter, the emergency-stop state, the daily loss cap, and so on are saved to a separate file for each combination of currency pair and timeframe. Even when running multiple charts on the same terminal, a settings change on one chart never affects another. The flip side of this is that if you want to trigger an emergency stop for a given currency pair, you must press the emergency-stop button on that chart individually — it is not automatically linked to other charts.
The acceptance-of-responsibility flag resets every time the EA starts: you must click the “accept” button in the Auto-Trading Settings Panel again every time the terminal restarts, the EA is re-attached, or the timeframe is changed. If you’re running on a VPS and it restarts unexpectedly, periodically check whether the acceptance has been cleared and auto-trading has stopped.
The daily loss cap’s counter resets on restart: as described in Chapter 5, Section 5-7, the daily realized-P&L counter returns to 0 when the terminal restarts, etc. Be careful when combining this with a VPS’s automatic restart settings.
Signals still fire and internal state still progresses during a banned time window: as described in Chapter 5, Section 5-5, this can cause you to simply miss an opportunity, since only the real order is blocked.
We recommend leaving the hard stop-loss ON as a general rule: turning it OFF removes the broker-side protection if the EA or MT4 stops running, creating a risk of unlimited loss.

Chapter 11:Handling Order Errors (Troubleshooting)

If an “ORDER FAILED” panel appears at the bottom right of the screen, the following are the typical causes (excerpted from the EA’s internal error-code reference table).

Situation	Likely Cause / Fix
Server not connected	MT4 is not connected to the broker’s server. Check your connection and login status.
Trade timeout / broker busy / requote	The connection or execution environment is unstable. Wait a while, or review your slippage setting (Chapter 5, Section 5-3).
Invalid stop price (below the broker’s minimum distance)	The SL the EA tried to set is closer to the current price than the broker’s required “minimum stop distance.” Review your stop-loss width setting.
Invalid lot size	The lot size calculated by the % Risk method may be outside the broker’s minimum/maximum lot range. Review your risk % setting.
Insufficient margin	Your account doesn’t have enough margin for the lot size. Review your lot size / risk % settings.
AutoTrading not allowed	Either the “AutoTrading” button at the top of MT4 is OFF, or “Allow live trading” is unchecked on the EA’s “Common” tab (double-check Chapter 2, Section 2-2).
Market closed	It’s outside trading hours — a weekend, a holiday, etc.

If only a numeric error code is displayed, look up that code in the MQL4 standard error-code list (MetaQuotes’ official documentation).

Chapter 12:Disclaimer

By using this software, “Band Walk Alert Tenkyo System Trade,” the user is deemed to fully understand and agree to the following.

On the uncertainty of operation: due to market conditions, network environment, changes to the MT4 platform’s specifications, VPS malfunctions, and similar factors, this EA may exhibit unexpected behavior — failing to enter as intended, failing to exit at the moment it should, or leaving a position unattended. These are either a matter of the program’s design or force majeure, and the author bears no obligation whatsoever to fix or compensate for any resulting opportunity loss, floating loss, forced margin call, or other damages.
On bugs and defects: being software, it may contain latent bugs or design flaws. Users must run it accepting the risk of “loss caused by a bug.” Providing bug fixes or updates is entirely at the author’s discretion, and is not a commitment to respond immediately to any user’s request.
Full responsibility for losses: any and all losses incurred through the use of this EA are 100% the user’s own responsibility. The author bears no responsibility whatsoever, under any circumstances, for any reason. Regardless of the scale or cause of the damage, the user is strictly forbidden from pursuing any claim for damages, refund, or complaint against the author, including on moral grounds.
Full self-management: lot sizing, risk management (including configuration of the various safety features in the Auto-Trading Settings Panel), and the decision to continue or stop running the EA are entirely the user’s responsibility. Be aware that any outcome resulting from leaving this EA unattended is the result of the user’s own choice.
Copyright and prohibited actions: all copyright in this software and manual belongs to the author. Regardless of the reason, unauthorized reproduction, duplication, distribution, resale, lending to a third party, and analysis of the source code (such as reverse engineering) are strictly prohibited.

The claim “I lost because it didn’t behave the way I expected” does not hold up in the world of investing. If you have even the slightest objection to this clause, you are prohibited from using this EA.