After you perform System Restore in Windows Vista, you are unable to install a Windows update, a hotfix, or a service pack. Additionally, you may receive the following error message:

80071A91 (ERROR_RM_NOT_ACTIVE)

When you try to install Windows Vista Service Pack 1 (SP1), you may receive one of the following error messages:
Error message 1

Installation was not successful

Error message 2

An internal error occurred while installing the service pack

There’s been plenty of talk about the first service pack for Vista. Conflicting information from Microsoft and others would have you believing there will be a service pack, there won’t be, or even that there already is one, all depending on the day you read the news. What should you believe? Keep reading →