The Error End Activation Key error may be caused by windows system files damage. The corrupted system files entries can be a real threat to the well being of your computer.
There can be many events which may have resulted in the system files errors. An incomplete installation, an incomplete uninstall, improper deletion of applications or hardware. It can also be caused if your computer is recovered from a virus or adware/spyware attack or by an improper shutdown of the computer. All the above actives may result in the deletion or corruption of the entries in the windows system files. This corrupted system file will lead to the missing and wrongly linked information and files needed for the proper working of the application.