If your Windows 7 upgrade has failed with message “The upgrade was not successful” and your computer reboots repeatedly, then this article may help you troubleshoot the issue.

Windows upgrade was not successful

When you try to upgrade a computer from Windows Vista to Windows 7, the upgrade fails and you receive the following error message:

• The upgrade was not successful.
• Your previous version of windows is being restored.
• Do not restart your computer during this time.

However, when the computer restarts, it does not roll back to Windows Vista. The upgrade process starts again and then fails with the same error message. This issue occurs repeatedly and the upgrade process is stuck in a reboot loop.

This issue may occur because the computer contains one or more shell folders (Documents, Pictures, Music, and so on) that are redirected to locations within their own paths.

To resolve the endless reboots, you will have to access the Windows Recovery environment, locate the duplicate folders, and then move the duplicate folders to a temporary location. After the system successfully rolls back to Windows Vista, you will have to take additional steps to avoid the problem before you upgrade to Windows 7.

For a detailed how-to visit KB978421.