Defrag won't so jack. It's not a tool to fix things, only to speed up hard drives.
Frankly this could literally by anything at all. Rundll32, as the name suggests, is a process which in the basic sense runs .dll files - 32-bit .dll files. Given that 80% of the system files on your PC will probably be .dll files you're pretty much screwed. It might not be the rundll32.exe file that's causing the problem - it might only be falling over due to a poorly coded or corrupt system file, which is why problems like this can be a nightmare to diagnose.
Your best hope is that you have a virus. You know you've got a horribly generic problem when the best case is a virus.
In order:
- Update virus definitions and do a full scan.
- Right click on every hard drive under My Computer (if you can access it at all - if not use Control Panel > Administrative Tools > Computer Management > Disk Management) go to
Tools, select
Check Now, tick the
Automatically fix file system errors box and hit
Start. It will likely ask you if you want to do it at the next start up as files are open, so do that and restart.
- Go and make a cuppa.
- Insert your Windows installation CD, go to Start > Run and type
sfc /scannow - this will search for corrupt or non-signed system files and replace them.
Cross your fingers that this fixes it. If it doesn't, just give up and use that backup I keep banging on about.
If not... well it's about time you had a nice clean Windows installation, isn't it?