I have an elderly Dell Inspiron 2500 Laptop running Windows XP, just about every time I apply Windows Updates I get boot problems. The laptop will partially boot but won’t get as far as the Windows logon screen. If I switch it off again and restart it sometimes fixes itself, but sometimes it doesn’t.
The problem seems to be caused by the Windows Update process updating the registry keys. Specifically HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Currentversion\Setup I don’t know if this is the only key affected but it was the most recent one I found.
I have managed to solve this problem by using Registry Mechanic from PC Tools Software to scan the Registry and then fix any errors it finds. You could do the same thing by using Regedit to edit the registry but Registry Mechanic is pretty reliable and seems to do the job for me.
I have now got into the habit of running Registry Mechanic after any Windows Update download. Sometimes I have had to resort to booting Windows in Safe mode to run Registry Mechanic but things have always come right after Registry Mechanic has worked its magic.
At the time of writing (June 2008) Registry Mechanic costs $29.95 and is available for a free trial download. If you are having the same problems as I have then it is worth the money.
There are other products which would do the same job just as well but Registry Mechanic is the one that I found when I initially discovered this problem and it has served me well since (but see the next post to avoid being ripped off by PC Tools).