Hey, I've seen that before, after changing the HAL on a physical computer. After some Google searching, I found some advice that seemed to help. The advice came in two parts:

1. Uninstall Windows Installer, reboot, manually reinstall it, reboot.
2. Manually re-register the DLLs that make up Windows Update, reboot.

You can download Windows Installer as a separate piece from here:

http://support.microsoft.com/kb/893803/en-us

In principle, that ought to do it. Some of our friends on the Internet recommend taking it one step further and re-registering the DLLs that make up Windows Update, using the regsvr32 command. You'll find a list of them in this dialogue:

http://forums.techguy.org/windows-nt-2000-xp/595966-windows-installer-3-1-will.html

Some combination of those actions fixed the problem for me. I wish I could be more precise; it was late, and I was getting sloppy.


If the XP->Vista upgrade uses Windows Installer, your problem could be related to the above. I myself have almost no experience with Vista.


You may have noticed that, during the reinstall of Windows XP, you are prompted for a new username, and you get logged in as that. However, you may well have been using Windows as a different user before, maybe even Adminstrator. Maybe your PGP keyring is stored under a different username, and needs to be copied over. If so, anticipate permissions problem: your new username may not have access rights to the old keyring file. Log in as Administrator, or a user with administrative privilege, and give the new user rights. Or just go back to logging into Windows using the old username.