Windows – Can I set an HTML file as desktop background in Windows 7

In the same dialog box that you mentioned about the "fix desktop icons" button, ensure that active desktop isn't enabled by unchecking everything in the list.

Next, go into the Registry Editor and check that there is not a key called 'NoChangingWallpaper' in either of the following locations. If there is, delete it and restart.

1. Click Start
2. Click Run
3. Type regedit
4. Click OK

HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\ActiveDesktop and HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\ActiveDesktop

Try resetting the Windows theme:

1. Right-click your desktop
2. Click Properties
3. Click the Themes tab
4. Select Windows XP from the list of themes
5. Click Apply
6. Restart your computer

Failing that, try an sfc /scannow to check for any corrupt system files they may be preventing the desktop wallpaper from automatically refreshing.

1. Pop in your XP installation media and cancel out of the installation wizard
2. Click Start
3. Click Run
4. Type sfc /scannow
5. Click OK
6. When the box disappears, restart your computer

If this does not work, try a system restore.

How to change the desktop background to a a solid colour

1. Right click on a blank area of the desktop
2. Select 'Personalise'
3. Click on the 'Desktop Background' icon at the bottom of the window
4. Under 'Picture Location' select 'Solid Colours'
5. Select the colour of your choosing
6. Then select 'Save changes'

You may want to use the 'More' option to choose a more specific colour/shade.

• Source: Windows 7 - How to change the desktop background to a a solid colour