The backup software would return FFFDFFC6 errors when trying to read certain files. These files were largely database and application tmp files. The problem happens because the files are in the process of being updated during the backup. If a file is being updated when the tsafs scans the file, it could be reported to sms as a 0 byte file. This happens because the file size is not reported to sms until the write to the file is complete and the file is closed. This could cause the sms read errors on database files, tmp files or any file that is open and being updated at the time of the backup. This can result in backup status information saying that the backup is incomplete. Nss volumes have functionality to help deal with this problem, such as copy on write (COW) and snapshots. The traditional filesystem does not have these features. Open file managers can have issues with this on traditional volumes as well. The best time to do these backups would be when as few files are open and active as possible. Or, move to nss volumes rather than traditional volumes. Even then, a good backup practice would be to have as few open files as possible. The old tsa600.nlm did not show this read error as there were no checks built into it to check for this condition. This could result in corrupt files in the backup. Tsafs has some functionality built into it to deal with certain open files such asGroupWise files. The tsafs /enablegw=yes accounts for open GroupWise database files and specifically exludes some GroupWise files that are not necessary to backup such as the ngwguard.rfl, the wpcsout and wpcsin directories because of this problem.