After searched this forum, I found two threads posted with the same problem. One has been solved, but with the warning that is was a specific solution to the poster. Others should post their own thread.
So here I am.
Problems occurred to me when I was trying to make a system backup. Windows told me, it could not perform the desired backup, because it was missing some files.
After performing sfc /scannow, this is what my system came up with:
Beginning verification phase of system scan.
Verification 54% complete.
Windows Resource Protection found corrupt files but was unable to fix some of them. Details are included in the CBS.Log ...etc...
I've added my zipped CBS.log
The system is a quite new Acer with Windows 8 preinstalled. I have reformatted the SSD drive into two partitions (shrinking C: and assigning the free space to a new D:) and installed some software. That's about it.
I surely would appreciate any help as I am out of options!