Hello,
Can you please tell us if you have recently installed updates for your Windows OS on the problematic machine? We had a similar report (with the same error) from another user who encountered the same error after installing several updates for his system. He was able to overcome the error by uninstalling all the updates he installed (there were quite many), but unfortunately we cannot say for sure which Windows updates may broke the system and generate this error.
So, what you can try is to uninstall the Windows updates you have recently applied on your machine and see if this helps. Also, you can take a look on the
".NET 4 fails to install because SECUREREPAIR fails to CreateContentHash" thread which could be useful for you.
Let us know if this helped.
All the best,
Daniel