Backup Fails

Dear Readers,

First of all, I hope this thread is posted in the right place.
If not, please accept my appologies, I am a newbie...
I could not find any topic that helps.
I have tried several times to make a backup, but every time it fails.
The directory I am trying to backup to, is empty.
I added a printscreen of the message, Calibre shows.
I appreciate any help!
Thanks in advance,

Harry

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