Need to roll back to a previous service pack or uninstall a patch? A new function with version 10 is the ability to unistall service packs. This is helpful if you run into an error or performance issue and need to test if the service pack is involved.
If you are using Windows XP, you can use the Add/Remove Programs window to view and uninstall service packs or patches. For more details visit this link.
But if you’re using Windows 7, the workflow is slightly different.
i) Open Control Panel
ii) Navigate ‘Programs and Features’-> ‘View installed updates’
iii) Navigate ‘ArcGIS Desktop 10 Service Pack x’-> Right Click and Uninstall.