MT4 Debugging

Migrate EA logic from MQL4 to MQL5 deliberately.

MQL5 is not just MQL4 with different function names. Position accounting, trade classes, symbol functions, and event handling are different enough to require a migration checklist.

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The developer has an MT4 EA and wants to adapt the logic to MQL5.

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Translate execution model

MQL4 OrderSend patterns often become CTrade calls or MqlTradeRequest structures in MQL5.

Replace order loops with position/order APIs

Use symbol-specific data functions

Check netting versus hedging assumptions

Rebuild indicator access

MQL5 indicators often use handles and CopyBuffer. Do not assume old direct indicator calls map one-to-one.

Create handles in OnInit

Release handles when needed

Check CopyBuffer return values

Retest risk logic

Lot sizing, stops, spread, and account metrics should be revalidated after migration.

Normalize volume

Validate stops

Retest max exposure

Log all migrated assumptions

Use the tool

Use Workfusion to review the migrated draft and find missing MQL5 structure before Strategy Tester.

Fix the first error first

Keep full EA context attached

Recompile before changing strategy logic

Open compiler fix desk Open related tool page

Related guides

Continue the EA build path.

Compiler Fixes

MQL5 CTrade include and trade object setup

Set up the MQL5 CTrade object correctly so Buy, Sell, PositionClose, and result checks compile cleanly.

Compiler Fixes

MQL5 OnInit and OnTick EA skeleton

A clean MT5 Expert Advisor skeleton structure for OnInit, OnTick, risk gates, signal checks, and execution.

Code Review

MQL5 code review before backtesting

Review lifecycle, execution, risk, inputs, and logs before spending time on MT5 Strategy Tester runs.