Boot Time Scan won't Run...

I’ve been using Avast for the past 5 or 6 years and never had a problem with it - overall, a great free product. After having an issue with my email, I wanted to perform a boottime scan to check for viruses. I scheduled the scan and rebooted my PC. After it starts up it freezes on the screen before the Windows XP splash screen (the screen it freezes on is the black screen with the gray bar along the bottom that usually fills up quite quickly - also, I actually have the windows splash screen disabled…not that that should matter). I’m able to run a scan while the PC is up and running with Windows, but some of the files can’t be deleted because they are in use, so I really need to run a boottime scan. Any ideas? Thanks in advance. If you need any info to diagnose the problem, please let me know.

Strange, if you have done it before…
Have you tried removing the infections with MBAM http://filehippo.com/download_malwarebytes_anti_malware/

Hi, I’m having a similar problem as the original poster of this thread. My issue seems to go much deeper than his though. I’m not sure if I should create a new thread or not.

Basically, after installing a Windows update today (through automated Windows Updates), and after restarting, my computer became very, very slow. I then restarted and got the blue screen of death (unmountable boot drive). I started up in Safe Mode and now:
avast! won’t do a boot time scan; I can schedule it but it won’t actually do it.
Online Armor won’t start.
Windows Firewall won’t start.

I have indeed tried to use MBAM (the only security device that would start and run properly) but I’ve had no success. I suspect that the unmountable boot drive is a symptom, not the root cause.

Does anyone have any tips on how I could get avast! to do a boot time scan successfully? Or any other advice?

I have Windows XP 32 bit. This is the second time I’ve encountered major technical difficulties after installing a Windows update, and no I didn’t download these updates from some random site or anything like that. The last time this happened was about a year ago (and I had to reformat, but I wasn’t using avast! at the time).

I’d really appreciate any help. Thanks in advance.