Hi,
Error 1410 Class Already Exists errors are caused by missing system files or if an application tried to register an application-specific window class with the system that had already been registered.
Please answer the following questions in order to assist you better.
- When do you get this error message?
- Are you trying to install any application?
You may run the system file checker scan and see if there are any corrupted system files.
SFC (**System File Checker)**is a tool which scans system files and replaces incorrect versions of the system files by using the correct versions.
Refer the following article for more information on using SFC tool to troubleshoot missing or corrupted system files:
http://support.microsoft.com/kb/929833
If you are installing or running an application, kindly contact the application supplier for further assistance.
Keep us posted on the status of the issue.