Common Setup & Connection Issues
"Cannot load libzmq.dll" or "unresolved import function"
The EA uses the ZeroMQ library to talk to brain.exe, which requires libzmq.dll and libsodium.dll to be present in MT4’s Libraries folder.
- Confirm both files are directly inside
MQL4\Libraries— not in a subfolder. - Fully close and reopen MT4 after copying them in. MT4 only scans this folder for DLLs at startup, not while it’s already running.
- Confirm Allow DLL imports is checked both globally (Tools → Options → Expert Advisors) and on the EA’s own properties (Common tab).
brain.exe never launches
- Double-check
AI_WORKING_DIRin the EA’s inputs points to the exact folder containingbrain.exe— this must be an absolute path, not a relative one. - Confirm
AUTO_START_AIis set totrueandAI_EXECUTABLEis exactlybrain.exe. - Check the Experts log (Ctrl+T → Experts tab) for the exact error message the EA reported when it tried to launch the process.
- Some antivirus software flags newly-downloaded executables on first run. If
brain.exeis being silently blocked, check your antivirus’s quarantine/history log.
EA runs but never places trades
- Confirm AutoTrading is enabled (green button in the MT4 toolbar) — MT4 blocks all order placement when it’s off, independent of anything the EA does.
- Check
MAX_SPREAD_PIPS— if your broker’s spread on the symbol regularly exceeds this value, entries will be filtered out. - Check whether
MAX_CONCURRENT_PAIRSorMAX_ENTRIES_PER_SYMBOLis already at its limit from positions open on other charts. - If the account drawdown breaker has recently tripped, new entries are paused for
DD_COOLDOWN_MINUTES— this is expected behavior, not a bug.
License key issues
Your license key is generated automatically at checkout and is always available under My Account → License keys. Every purchase includes one license, usable on up to 3 MT4 accounts at once. If you’ve reinstalled on a new PC, VPS, or account and are told all slots are used, you don’t need to contact support — go to My Account → License keys and click Deactivate next to an account you no longer use, then try again.
Starting the AI's memory over
If you want brain.exe to forget everything it has learned so far — for example after switching brokers or accounts — close brain.exe first, then run Reset-Brain-Memory.bat from inside your install folder. It only deletes files in that folder and asks for confirmation before doing anything.
Backtest engine (“brain_backtest.exe”) issues
- “Backtest brain already running on port 5655. Connection successful.” — this is not an error. It means an earlier
brain_backtest.exefrom a previous run is still active and the new one connected to it instead of starting a duplicate. If you wanted a completely fresh run, close the existingbrain_backtest.execonsole window first. - No
backtest_statefolder appears after a run — confirmAI_EXECUTABLEwas actually set tobrain_backtest.exeon the Backtest EA’s Inputs tab. Its default value does not launch a process automatically. Merge-Backtest-To-Live.exereports “No backtest_state folder found here” — it only looks in the folder you run it from. Make sureMerge-Backtest-To-Live.exe/.batlives in the same folder asbrain_backtest.exeand itsbacktest_statefolder, not somewhere else.
License errors
- “license.txt not found in this folder” — rename
license.txt.exampletolicense.txtin the same folder asbrain.exe, and make sure bothLICENSE_KEYandACCOUNT_NUMBERare filled in. - “Invalid license key” — double-check you copied the key exactly from My Account → License keys, with no extra spaces.
- “X/X accounts – you have used all your license slots” — this license is already active on its maximum number of MT4 accounts. Go to My Account → License keys and click Deactivate next to an account you no longer use, then restart
brain.exe. - “could not reach license server” — this is a warning, not a hard failure. brain.exe will still start; it just couldn’t re-check your license this time (usually a temporary internet issue). It will check again next time it starts.