I have written a Perl scripts which connects to my Cerberus FTP Server and downloads files and at the same time sends MDTM command for each file. I recently found out that Cerberus FTP Server reports invalid path when i try to MDTM command on a file. The strange part was that a GET command on the same file works fine as you can see below:
[SEND] RETR /data/users/bic/S900HR9L_TEST AF FORTYNDING.txt
[RECV] 150 Opening data connection
[RECV] 226 Transfer complete
[SEND] MDTM “/data/users/bic/S900HR9L_TEST AF FORTYNDING.txt”
[RECV] 550 MDTM failed: Invalid path
Then i tried same scenario with SlimFTPd, sending MDTM on a file with and without spaces and there it works just fine.