Xp Crippled After Today's (april 10) Update

I don't auto-update; I updated in the morning, and it didn't ask for a reboot. Later I switched off the computer and when I started it again after two hours, it just won't start. It reaches the desktop, but the Taskbar is just shown as a plain blue bar, all the icons on the desktop have the default unrecognized file icon, and while the mouse moves, nothing is clickable and no keyboard keys work. It just stops at this point, and even after waiting for five minutes, it remains the same. I have to manually reset the computer, and I did it quite a few times, and tried the last good configuration that worked, but to no avail.


I went to Safe mode and disabled Bitdefender and Comodo Firewall in the autoruns, then restarted, and the PC immediately started normally, loaded the desktop, and now works perfectly. But when I manually started Bitdefender, it wouldn't start, saying the vvserv (or whatever the name is) service was unavailable. I realized that I had also disabled the services in msconfig, but when I opened the services window (services.msc) and tried to set the Bitdefender service to manual or automatic, it says access denied, even though I am using an administrator account.


I tried a repair install but the problem remains the same. If I disable Bitdefender at startup, the computer works as usual.


Is there any way to uninstall the update? Or will I have to uninstall the whole app and reinstall it again?


When I searched for 'bitdefender update" on Google, it came up with many pages saying an update had clobbered Windows PCs on 20 March.