Only C:\drive full backup is failing with error

Honestly - what kind of help do you expect with this kind of 'fragment' ?

Is it more than 'It does not work' ?

And be so kind to ask yourself what others might need to know to try to help you.

Which OS version ? - obviously 'a Windows brand'

Which NW version ?

A separate client or the backup server itself ?

Has the backup ever been successful before ?

When does it fail ? - at the start/middle/end ?

Does it fail at a certain file? - if so, can you repeat that ?

Does a manual backup work ?

At the client please run "save -v -s server C:\" to verify that.

If this happens only for C: this is obviously not an error of general behavior.

Have you ever considered to check the filesystem ?

The problem with the backup of this client is that only c:\drive full backup is failing with the error mentioned above.

All the other drives and vss are successful

incr backup for c:\drive & other drives are successful.

Only the full backup for c:\drive is failing.