Audience
For MT4 developers fixing legacy EAs, partial snippets, or broken MQL4 logic.
MT4 EA debugger
Clean up MT4 EA code before the next compile pass.
Debug MQL4 Expert Advisor code, identify missing functions and risky patterns, and generate a cleaner MT4-ready draft.
Paste MQL4 code and errors
Get issue and fix lists
Flag martingale/grid risk language
Prepare cleaner code for manual MetaEditor testing
Problem
MQL4 projects often mix old patterns, missing guards, and unclear order handling that make debugging slow.
Outcome
Workfusionapp reviews the code, explains likely failures, and returns a safer draft with clearer structure and checks.
Workflow
From MQL4 error to a focused MT4 repair path.
The MT4 debugger should send each visitor to the matching blocker: OrderSend error 130, magic-number order management, migration drift, or a cleaner compiler-review loop.
Step 1
Paste the broken EA
Step 2
Add compiler errors
Step 3
Generate a fixed draft
Step 4
Review and test in MT4
Related resource cluster
Move from this page into the full blocker set.
Use the cluster hub when the first issue branches into adjacent compiler, draft, risk, or review checks.
MT4 cluster
MT4 debugging guides
Use this hub for OrderSend 130, MQL4 compiler errors, magic-number ownership, and MT4-to-MT5 migration checks.
Open MT4 cluster
Compiler cluster
MQL compiler fixes
Use this hub for undeclared identifiers, CTrade setup, CopyBuffer, invalid stops, invalid volume, and fill-policy blockers.
Open compiler cluster
MT4 debugger handoff
Choose the MT4 blocker before rewriting the EA.
Start with the first MetaEditor or Journal evidence. Keep the EA review narrow, then move to manual MT4 compile and tester work.
OrderSend error 130
Use this when MT4 rejects SL/TP because stops are on the wrong side, too close, or not normalized for the symbol digits.
Magic-number order management
Use this when the EA mixes orders, cannot separate strategies, or needs safer filtering before closing or modifying trades.
MQL4 to MQL5 migration
Use this when the blocker is not pure MT4 debugging but migration drift between OrderSend patterns and MQL5 CTrade workflows.
Send me the MT4 debug workflow
Opt in only if you have an MQL4 EA that needs focused repair around compiler errors, OrderSend failures, magic-number management, or migration cleanup.
Intent locked: Paste compiler errors
Lead activation handoff
No email wait is required. After saving the opt-in, continue into the free desk with the same blocker so the visitor-to-lead-to-workflow path is measurable.
Continue in free deskChoose the workflow you want, then opt in only if you want Workfusionapp updates.
Does compiler-worker support MT4?
The compiler worker path is currently optimized for MT5 .mq5 compilation. MT4 code still gets debug and static review.
Will it rewrite unsafe sizing?
It flags dangerous patterns and pushes the draft toward explicit risk controls.