Welcome to Justanswer.com, my name is Dustin.I'm sorry to hear about the issue you are having, I will do my best to help you resolve it.
I am assuming this is happening on your windows 7 computer..
Are you saying its been stuck on the same erasing updates screen for three weeks?
Or are you saying everytime you shut it down and it tries to install updates, it goes back t o that screen and never installs them?
Thank you for your response,