Without more information it would be impossible to answer your question accurately. I would first check with your systems administrator to see if any changes have been made recently that may affect your System i FTP server. Some possible causes – improper syntax; lacking ptfs; application administration; folder permissions, object availability; unrelated network issues; Just to name a few. The error message you listed is part of a standardized FTP error messages for any platform. 426 indicates that the connection was closed and the transfer was aborted. Now you just to find out why.