This machine was blue screening on start up (can't remember the exact error) so I did a repair install.
Once it got to the please wait screen nothing else happened, the mouse would still move but it wouldn't progress any futher.
After some time I did a hard reset. It then went to the login screen and I logged in. It asked me to activate Windows before proceeding to which I said yes (this is a legit OEM Windows) but nothing happens after that. You just get the desktop back ground, no task bar, no Ctrl, Alt Del nothing...
I tried a few things including re extracting the wpa.dbl file from the install CD. I tried a second repair with a different XP disk.
The 2 disks I have used are XP SP3 OEM, and the machine is also on SP3.