CobianSoft

NTFS and Windows don't use UTC time by default (it can). Most Linux systems use UTC. Could that be the problem?

The copy of the files is provided by CopyFileEx API function , so it's the operative system which actually is copying the files. So if the OS does some optimization behind the scenes, the the program is also using it, indirectly. No additional optimizations are done.

I don't see any problem with the configuration. Perhaps the problem is in the history of the task. Are there some old backups in the task that maybe don't exist anymore?

I would begin by changing the installation mode from Service to Application to see if the problem is solved.

Not without a backup no...

Is the Clear archive attribute on the Advanced tab set?

This happens only with "Common folder names" i Windows: Documents and Desktop will always show that name on Explorer even if the names are some others. To solve that you need to exclude the file desktop.ini. Add this file as a mask in your exclusion list.

I find the search function of this forum to be quite limited...

The red flag indicates that the files created by the backup should never be deleted. Just a way to keep some backups safe.

Exactly. This is the way the client has to know what host to connect to.