When you try to remove Plus! for Windows XP, you may receive an error message that is similar to the following:
1635 This patch package could not be opened. Verify that the patch package exists and that you can access it, or contact the application vendor to verify that this is a valid Windows Installer patch package.
This behavior may occur when the following registry key is damaged:
To resolve this issue, remove the damaged registry key, remove and reinstall Plus! for Windows XP, and then remove and reinstall Plus! for Windows XP again.
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows
Remove the Damaged Registry Key
Click Start, and then click Run.
In the Open box, type regedit, and then click OK.
In Registry Editor, locate the following registry key: