


Of course, this link is likely to die at some point, and I have no XP boxen to test it from. It also has lovely logging, and lists of file locations and it lists as the location for windows XP SP3. This is the best option since it should get your system as patched up as possible, and lets you do so even if XP patches are no longer hosted if you already downloaded them.

This should get your XP box completely up to date, and as of mid december 2016 (when I'm posting it), it seems to update still. Since its downloading the updates directly from MS, and gets the full/offline installers and automatically applies them, these are the official updates and you don't need to rely on windows update for at least the initial update. You need version 9.21 or older as its the last version that supported XP. I use an archive I built from an outdated version of WSUS offline update - in case I need to stand up a windows XP system.
