BSOD on Windows 7 64 bit at aswRvrt.sys

Hi.
On a clean Windows 7 64 bit machine I suddenly get BSOD (stop 0x000007B) and trying safe mode shows loading up to aswRvrt.sys.
Repair fails and system restore to before Avast was installed also fails (reason, something like cannot remove directory D:\ !)

History is that I installed WIndows 7 on a new hard drive, run a few gigantic Windows updates, installed Avast.
After having problem seeing a USB3 removable drive I installed all HPs storage drivers (laptop is an Elitebook 8460p) and the new SATA-driver required reboot. After reboot the BSOD was a fact.
I can still boot my Linux OS on the same drive.

I tried following http://support.microsoft.com/kb/922976 but the HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Msahci data-field is already set to zero.

Is it possible to disable avast loading at boot time to uninstall it? I downloaded awastclean.exe and put it on my harddrive but when booting into system recovery with cmd-prompt it couldn’t run the executable (non-existing sub system)

Any suggestions besides reinstalling Windows 7?
/Peter

I attach a FRST.txt log

This will disable Avast services etc… and also remove a few bits of adware

Download the attached fixlist.txt to the same location as FRST
Strat FRST and press fix
On completion try a normal boot

Thanks!
I run the fixlist and it went well. However, I still get a BSOD, this time from ClassPnP.sys.

A curious thing is when I start up in recovery mode my C:-disk seems to be the boot-partition (Dir gives nothing) and D:-disk seems to be the system-partition (contains windows-folder etc). However after launching FRST64.exe it dies and then the drives has switched drive-letters and I have to run FRST64.exe again.

I read someone else having this type of problem because drive-letters changed. I tried to manually switch C: with D: in the registry HKLM\System\MountedVolumes but after a boot attempt they were switched back! What is the normal disk-configuration with Windows 7?

C:\ is usually the WIndows directory unless you have 2 different Hard Drives. (I have 2, C:\ is Windows, J:\ Is A Partitoned Drive from the C:\ and an I:\ which is an SSD.

Prior to the aswrvrt.sys issue, what happened? Any unexpected power loss during boot?

What drive is set in bios as your boot device ?

I only have one hard drive but with several partitions. I first installed Windows 7 and it created two partitions, one small one (perhaps with boot loader and recovery tools) and one big one with the system files.
When looking into HKLM/System/MountedVolumes I can see that it (at least nowadays) labels the small one C: and the bigger one D:.
I also have an extended partition containing Linux logical partitions and the MBR in first sector is replaced by the Linux GRUB but all that has been working fine and I have the same setup on work.

The problem started after installing the SATA-driver from HP-site:
http://h20564.www2.hp.com/hpsc/swd/public/detail?sp4ts.oid=5056947&swItemId=ob_92085_1&swEnvOid=4059#tab4

Regarding the boot and system partitions under WIndows 7 I found (http://www.multibooters.com/articles/windows-drive-letters.html)

“From Windows-7 the default letter allocation order for system and boot partitions has been reversed. Now the Boot partition gets priority and will be assigned C: while the system partition comes second and gets D: - that is if it gets a letter. If the System Reserved partition is small and houses only a few boot files then Windows will deem that it holds nothing the average user needs access to and so will not assign a drive letter, thereby removing it from being visible in Windows.”

which seems to indicate that my drive letters are fine?

Hmm, actually after reading http://www.multibooters.com/articles/windows-drive-letters.html again I see that

"The system partition is now called the System Reserved partition and this will house the bootmanager files of the Windows install, with the operating system itself being on the separate Boot partition. Hence the old way of re-assigning drive letters in the order of system partition as C: and the boot partition as D: would always be wrong and clearly needed to change. "

actually means that I do have the reversed drive-letters on my PC!

The question is then how I do reverse this since my first attempt to manually change them was undone after next reboot. Maybe try deleting all lines as was suggested here http://www.multibooters.com/tutorials/recover-from-a-changed-windows-drive-letter.html, of course i would export the old settings first to a file.

Anyone here with more insight into the drive-letter details of Windows 7? Why did it change and how do I make sure it is setup correct? Weird also that running the FRST64.exe actually seems to cause the drive letters to switch!?

FRST is only a scanning tool. FRST shouldn’t be switching drive letters. If it is, it’s a new thing.

Can you check in the bios as to whether your hard drive is set to ide or sata

I have it set to SATA but tried IDE also when it failed to boot.

I have some more info regarding the drive-letter mess and this is how I understand it

When I boot up using recovery tools I boot using X: and I find a small C: (no filesystem, system partition) and and large D: (Windows, boot partition).
If I run regedit here I probably see X:'s registry database which shows exactly those drive letters.

When running FRST64.exe it calls som API that makes drive letters switch. Afterwards, the former C: is gone, the former D: is now C: and contains Windows, X: is left as it was and the former C: is moved to Y.
Running regedit now shows my real disk-config with C: as windows and no D:.

Not sure this is related at all to my problem. But one odd thing is that when I tried a system restoration earlier it failed claiming it could not remove the folder D:

Starts to look like I have t do a full system reinstall :frowning: But it would be good to know what caused all this.

The way FRST works is that it ignores the system partition and looks for the windows one, now as you also have a grub bootloader there may lie a problem in that area

But Grub is (AFAIK) only replacing the normal bootloader on MBR which is placed on first sector or the disk and not in any partition.

Anyway, I am not sure the drive letter mess is related with my problems. Seems like I have the same type of problems as many other with Windows 7 and BSOD, like the other thread
https://forum.avast.com/index.php?topic=162525.0 which is developing exactly as mine.

There are unfortunately a myriad of reasons why systems fail to boot and sometimes it just happens for no apparent reason, this is why I advocate taking frequent disc images. There are several good free programmes for this

Ok, thanks for all your help everyone, especially essexboy.

Sorry I could not be of more help

Well this Windows 7/Avast BSOD seems to be an recent epidemic so I guess we start will see a solution to it.
I’ll run my Linux meanwhile since I suppose a clean install will end up in the same place when the Windows update has reach the same point.

It is not really an Avast problem. The file that is loaded just prior to the avast one is mup.sys

So a system without Avast will halt there and a google search for that error returns 28000 results https://www.google.co.uk/search?q=mup.sys&sourceid=ie7&rls=com.microsoft:en-GB:IE-Address&ie=&oe=&gfe_rd=cr&ei=ZfGKVN_PJ4zDbL3wgKAG&gws_rd=ssl#rls=com.microsoft:en-GB:IE-Address&q=safe+boot+stops+at+mup.sys