Cant Update Library

Do you let your computer enter the suspend/hibernate state when its not in use?
When did you last time perform a full machine reboot?
Do you have an additional internet filter somewhere in your home network?
How much free space is left on drive C: ?

If nothing helps, I’m afraid you need to try Method 2.2 from this post: You need to reclaim your server, but don’t dare to touch the Windows Registry