MT4 · Runtime errors
MT4 5009 · File must be opened with FILE_WRITE flag | YI GOLD
ERR_FILE_NOT_TOWRITE
Official meaning
File must be opened with FILE_WRITE flag
Possible causes · YI GOLD suggestions
Paths, access modes, formats, handles or permissions do not meet requirements.
Troubleshooting · YI GOLD suggestions
Check permitted terminal sandbox paths, names, access flags, formats and handles. Record open failures without granting permissive directory access.