Hi,
This was previously posted by Mark Salloway MS-MVP (XP)
This occur after installing SP1 when you are running a non Microsoft
visual
style and the folder
containing the customized styleshell.dll has a differing name from the
themes name (as shown in the appearances tab).
To get rid of this error you can switch back to a Microsoft Theme or
goto
/WINDOWS/Resources/Themes/<Name of theme in use> and rename the shell
folder
to the name of the visual style shown in the appearance tab.