A friend gave me his laptop because he was having some problems, so gave it a go, but I couldn’t fix it. The laptop freezes when I log into windows, nothing works - keyboard, mouse, nothing… I restarted it a few times, didn’t fix anything. So I ran it in safe mode, when it loads the drivers it gets stuck on aswrvrt.sys and freezes again. I tried rescue disks but they somehow freeze too, can’t load correctly. Also tried to disable avast before it launches but i have only a couple of seconds which are not enough. I can’t seem to think of another way to fix it so… I need your help. The system is with Windows 7 Ultimate 32-bit, Intel Core Duo T2400, 2GB RAM if that helps.
Cheers.
Download and save to usb the removal tools for all AV’s used on that system from another system if possible, while in safe mode you should be able to uninstall avast and once restarted run the removal tools to clear out remnants ( a further manual search for remnants wouldn’t hurt either )
Once all cleaned up you should be good to go with a new install of avast 
Well…I managed to delete avast but it didn’t fix the problem entirely. It freezes again, ran it in safe mode and now when loading it stucks on CLASSPNP.sys 
When I run it normaly is logs in and I’m able to move the mouse…a bit then freezes again. I noticed that the HDD light goes off when it freezes, so opened it up tried to clean it a bit, put it back still the same problem…maybe something is wrong with the drive?
There is a lot of info on CLASSPNP.sys available via google, seems to be an issue caused by a windows update.
- Power on the laptop
- Press F12 key to enter the BIOS
- Go to “Advanced” menu
- Go down to “System Config”
- Change SATA Controller from “AHCI” to “Compatibility”
- Press F10 to save and exit