Hi all. I have recently had to re-install Website X5 Evolution 11, and once I have registered, upon first opening of the program I am advised that there are now updates - which I have downloaded. However - when I then try to open the program to use it I am getting this error message:

"An error occurred when running the program.
Please reinstall the program. (could not load file
or assembly 'system.IO. Abstractions, version = 2.0.0.103,
culture = neutral, PublicKeyToken= d480b5b72fb431da'
or one of it's dependencies. The loaded assembly's maniftest
definition does not match the assembly reference.
(Exception from HRESULT:0x80131040)"

Can someone tell me what this means and how I can avoid it?

Thanks