Method 1
Right click on a blank area of the desktop and select Properties.
Now select the Desktop tab, then press the Customize Desktop button.
Now press Apply.
Your Active Desktop message should have disappeared and you should have your standard desktop back.
If Method 1 did not work, try Method 2.
Method 2
Open up your registry: Start -> Run
*Warning: Be careful what you are doing when in the registry. It’s very easy to make your computer non-usable if you edit the wrong entry.
Type regedit
Expand the following:
HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Desktop\SafeMode\Components\
Double-click on DeskHtmlVersion, select the Decimal radio-button, and change the value from 272 to 0.
Then press OK.
Close out of Registry Editor, click in a blank area of your desktop, and press F5 to refresh the screen.
You should be back at your normal background/wallpaper.