If it were my project that had this issue, the first thing I would do is check the logs in CFAdmin to see if the 302 is making it back to the CF server. If nothing is there, then check the webserver logs for the 302.
302 is a temporarily moved, please redirect error message. Have the webserver settings/config been recently altered?
I would request for the logs files from my customers and check.
I got the exception log files, and the following is the error information I got from it.
The cause of this output exception was that: ClientAbortException: java.net.SocketException: Connection reset. The specific sequence of files included or processed is:
All we do is using CFFILEUPLOAD, the user will select the files to upload, these files will be uploaded into the Server, ( are our requests been rejected by Server??)
I would try to get the web server logs.
Connection reset, probably by some kind of timeout, I'd guess. Are the files just being uploaded and stored on the server? Or are they being inserted into a database? Do the logs show anything about "connection reset by peer"?