FTPeek won't upload some .jpg files

[Dave Nicely]

Scratching my head on this one. I'm running a server side script that uploads hundreds of .jpg files to a remote ftp server. For some of .jpgs files, the upload just fails. I'm using a calculated file path reference, but have hard coded it to confirm it's not a reference error. I've check the 360 log file and there's no error message recorded. On the remote ftp server, the connection eventually times out due to my script trying to upload a long list of .jpg files (all of which fail). Any thoughts on why the upload would file are welcome.