Do a Ctrl+Alt+Delete and look in the process tab. click image name to organize it in alphabetical order. you will see explorer.exe somewhere in there. Click it and click End Process at the bottom right. If you do not see explorer.exe then skip this step. Now click the Applications tab and you will see 3 buttons at the bottom called End Task, Switch To, and New Task. Click New Task. A small window will open up that says Create New Task. In the white bar type in explorer.exe and you will have your desktop back. Sadly, you will have to do this every time you log on.
If that doesn't work, we'll try with something else.