I normally assume my Windows updates will occur with a minimum of fuss and bother, and in fact it took me several rounds to even realize what was going on this morning. I kept getting an “updates ready to install” notice, and I kept telling it to install. I was too busy with morning activities (on which I’m still behind) to notice what was happening.
The security update (Security Update for Microsoft .NET Framework, Version 1.1 Service Pack 1 (KB928366)) was not installing, but the install window wasn’t indicating this. So each time I closed it, it simply went back to notifying me I needed to install. So I began searching for some help on it, and I found this site that explains something about the error, and provides one fix. Unfortunately, though the comments indicate that solved some problems (the error you receive, 0x643, is generic), it didn’t solve mine. It did, however, help me head in the right direction.
Try his stuff first. My solution here is pretty drastic!
I had to go through Microsoft’s full procedure to manually uninstall and then reinstall the .NET Framework 1.1, then Service Pack 1 for it, and finally the security installation. If you find that the solution at the above blog doesn’t do it for you, you can consider trying this:
It looks long, but it is not really all that difficult. The problem I had was that once I had uninstalled and reinstalled the Framework, I also needed to add the service pack, which is not mentioned in those instructions. I should have thought of this myself, but I didn’t. In any case, you can find SP1 here:
So when you complete the instructions that begin with the label “Manually remove and then reinstall the .NET Framework 1.1”, install the service pack, and then go back to the Microsoft update page. That solved the problem for me. There are, of course, no guarantees.
On a probably unrelated note, my Windows XP chose this moment to tell me my hardware had changed too much since I activated Windows XP, and to require me to reactivate. The reactivation was no problem at all, but since I hadn’t changed any major hardware for months, it was kind of annoying. It may have had to do with the diagnostic startup that’s required in step #6 of the instructions.