MT5 · Runtime errors
MT5 4521 · File not found in the MQL5\Files directory to send on FTP server | YI GOLD
ERR_FTP_FILE_ERROR
Official meaning
File not found in the MQL5\Files directory to send on FTP server
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.