How to remove a corrupt SQL Server 2005 Express Instance?

• Download msicuu2.exe from http://support.microsoft.com/kb/290301
• Remove the highlighted programs as shown in the picture.
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• Completely delete C:\Program Files\Microsoft SQL Server
• Install SQL Server Express Edition again.
• If instance error comes then remove the services.

How to Delete / Remove Services in Windows XP and Vista

1. Go to Start > Run > services.msc to start Services applet.
2. In the Services applet, find the service that you want to delete permanently, right click it and click on the Properties from the menu.
3. In the properties window, find the name of the service and copy it to your clipboard.
4. NOTE : ITS Service NAME / NOT the display Name.
5. 
6. You may also want to stop the service, if it is running; this will kill all the running processes for it.
7. Open a command prompt by going to Start > Run > CMD
8. Once a command prompt has opened up, type the command “sc delete service name” without the quotes, replace service name, with the name of the service you copied in above step.

Note : Once a service has been deleted you should see a message saying “[SC] DeleteService SUCCESS”, this should mean that the service has been deleted, to ensure that, just click on the refresh button in the services applet and confirm that the service has been deleted.

Description of the Windows Installer CleanUp Utility

SUMMARY :When you are working on your computer and installing a new program, the installation suddenly fails. Now you are left with a partly installed program. You try to install the program again, but you are unsuccessful. Or, maybe you have problems trying to remove an old program because the installation files are corrupted.

Do not worry. Windows Installer CleanUp Utility might be able to help. You can use the utility to remove installation information for programs that were installed by using Windows Installer. Be aware that Windows Installer CleanUp Utility will not remove the actual program from your computer. However, it will remove the installation files so that you can start the installation, upgrade, or uninstall over.

You can download Windows Installer CleanUp Utility from http://support.microsoft.com/kb/290301