After using the very early Pending.XML file edit fix as described in my earlier blog the Windows 7 PC would be left in a torn state. This meant that Service Pack 1 could no longer be installed on this PC, and possibly other patches as well.
There are two options for recovering from this.
First, you could reimage or rebuild this PC. This is often not a solution, especially if there were vaarious bits of information that could not be easily reinstalled.
The other option is to repair the current system. Some people have had success in using a Windows 7 SP1 DVD or USB to do a repair install over the top of the current installation. If that does not work, Kelvin Aston provides a step by step set of instructions for repairing the system here – http://kelvinaston.blogspot.com/2011/04/possible-fix-for-torn-sp1-machines.html
Note: I have not been able to find a PC in a torn state in order to test out this fix myself.