Hi, Im new, so hello. It's a really nice forum. I just wanted to say that.

My problem is I'm having a blue screen with error 0x0000007b, and I may have the key in solving: I used avast to scan and it reported c:\pagefile.sys as a trojan (bifrose or something like that), so it asked me if I wanted to move and rename, and trusting that it's been enough time for avast to know how to play with vista, I thought I should...so it moved and renamed pagefile.sys.

Also, I scheduled a bootup scan after avast was done. I think its what caused my blue screen of love, and I would like to know how to uninstall avast from a bootcd (or any other method to uninstall avast)...

When I go to my vista bootcd, it sees my vista installation on the first or second screen, after it asks for the language and I hit repair, but then I do bootrec /rebuildbcd, and the cmd prompt shows that no windows installation is detected. How is that possible? it gave me the option to select it in the menu right before that.....

8 Years
Discussion Span
Last Post by kaninelupus

Hello rob331. I feel your pain. The file "pagefile.sys" deals with virtual memory. It compliments your RAM by using hard drive space as more memory. Therefore it is definitely not a virus or malware of any kind.
You might try this approach. If you have a Vista DVD try Startup Repair. If that doesn't work, try Safe
Mode>System Restore from the Recovery Environment, and you always have the
F8 advanced options and a repair install (with the DVD) as well.

***Startup Repair and System Restore from the Win Recovery Environment on
the DVD***

You can run Startup Repair by putting your Vista DVD in after the
language screen in setup. You can also run System Restore from the same

You run the startup repair tool this way (and system restore from here is
also sometimes effective):


How To Run Startup Repair In Vista Ultimate (Multiple Screenshots)

Note The computer must be configured to start from a CD or from a DVD. For
information about how to configure the computer to start from a CD or from a
DVD, see the information that came with the computer.


Well, the repair startup option is not working, it says its unrecoverable or something like that, so I think its avast and the boot time scan I scheduled after it finished moving and renaming the pagefile.sys (last time I could use the vista partition)....so how can I remove or disable all avast stuff if I still have access to the partition (using ubuntu on multi boot)? I want to start by doint that, but short of just erasing avast from program files, I don't know what to do to cause it to not startup (I think that may be the problem, a boot time scan).


The error you're getting is the error code for an inaccessible boot device, where exactly do you get the error? Can you boot up in safe mode for example? As atleast with safemode AVG won't be starting up, only necessary system drivers are loaded for safemode, no programs. If not then perhaps a chkdsk &/or fixmbr in the recovery console may atleast help.


well that helps. I can't go into safe mode, so i assume it's not the antivirus (assuming it didn't cause a bad registry boink last time I logged off when it said it would run a boot time schedule). Any way I could troubleshoot this in steps?



Couldn't be bothered to type it all out myself, while that is for XP, it's very similar with Vista... It is only a theory as I don't know exactly how it's starting up, when the error is happening & so on to make any further speculation of cause.


so im still trying to avoid reinstalling vista, so is there a way to trouble shoot this to get a narrower diagnosis?


I hate to say this but. In the interest of time it may not be a bad idea to proceed as you were thinking. Using ubuntu on multi boot or some other Linux disk to boot up and access your C:\ drive. At that point you could remove enough components from your Program Files/Avast folder to effectively disable it. Preferably placing a copy of the files in another folder (maybe in your documents) so you can replace them after windows is back up and running. That way you can do a complete uninstall of Avast.

Once Avast is disabled you can try booting up. If you can't boot you can work from this article to do a "Start up Repair"


did you already tried to move and rename the paging file back?

dismount the HDD
re-mount the HDD on a another computer or a external HDD
move and rename the paging file back to the previous name.
re-mount the HDD back to your computer and try to boot in safe mode to remove Avast.

Good luck !


How have you made out with your problem? If you were successful please share with us the procedures that finally worked. It would be useful for future reference.


Hate to say it, but using a Linux Live disc to recover your data and then reinstalling is by far the best option.

By the time you spend all that time digging out Avast (which by the way will likely cause more issues as the registry will go nuts over all the by now invalid entries - and no way to clean the reg without actually booting into the relevant OS by the way), you could have performed a clean install several times over.

It sucks I know, but you'll know for next time mate ;) As a replacement to Avast, have a look for a copy of Symantec Endpoint Protection (corporate level AV suite, so much lighter on resources than your retail suites). As a free alternative, have a look at Comodo -and for God's sake, stay away from AVG.

The other suggestion, seeing as ur already looking at a fresh install, would say consider Win7. Even at the RC stage is a massive improvement on Vista - much better hardware support (most of my hardware actually runs better on Win7 than on either XP or Vista) and rock solid. If you can go x64, even better :)

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