My Device Manager is disabled

Hi Wendy,
It sounds as though you have Windows 7 Starter. Is that correct?
If so, there is no personalization. However, you can get around this very easily by downloading Oceanis, it's safe, it's free and has been a solution for so many people with the same problem as you.
Here is the link: Oceanis
When you have downloaded it, you will be able to change the desktop background and there is also an optional desktop slide show (shuffle).
Let us know if that solves your problem. If you don't have Windows 7 Starter, then your problem will have to be resolved another way. Please come back and let us know if that is the case. 🙂
