View Full Version : Boot problem

19-05-2014, 08:42 PM
Got a Vista system here that wouldn't boot because of a stop 7B, second param 34, error.

Using a magic repair disk I did a fix mbr and after that it booted fine.

Ran chkdsk - fine.
Installed and ran MBAM. Showed 40 problems, most of them PUPs but some looking more dangerous. Let MBAM fix them but since then I haven't got past the driver downloads leading to the stop 7B BSOD.

I have tried fix mbr and boot sector but no change. I have tried Repair System from a Vista install disk. Took quite a while but it didn't fix it.

I have reset BIOS to defaults. Also re-seated HDD plugs.

Currently I have it on USB to my comp and am imaging the partition. This seems to running fine at 40% ATM.

This error could be a disk dvr problem I have seen. But since I can't boot it it is a bit difficult to look at the dvrs.

Any good ideas? I am running out of these so need some inspiration!


Speedy Gonzales
19-05-2014, 09:20 PM
A 7B stop error is usually a SATA driver stop error. Whoever installed Vista changed it to IDE mode in the BIOS. Installed Windows, then changed it back to SATA/AHCI in the BIOS. Thats what happens it crashes with a 7B stop error.

Change it to IDE mode in the BIOS, it'll probably boot

19-05-2014, 11:28 PM
Thanks, Speedy, but this is a fairly old installation that has just started to play up. And I did have it booting after the mbr fix but it is a no-go ATM. Drive is set to IDE.

It loads the drivers but then crashes. Seems like a MBR issue - can't find where Vista lives? The first MBR fix did get it booting but nada after that MBAM restart.

The drive is OK - imaged fine. Scanned with MBAM again via USB. Just won't boot.

20-05-2014, 08:18 AM
Should restore all the quarantined items in Malewarebytes skipping the obvious ones and see what happens then sort it from there

If you are using Malewarebytes 2.00,pays to be very careful with the PUP's as you can take out to much,just got my dual boot back after it took out a Registry key

Just to add try EasyBCD https://neosmart.net/EasyBCD/ This got my dual Boot back

Speedy Gonzales
20-05-2014, 08:21 AM
Run tdsskiller on it if its the main hdd. 7b stop errors may also be caused by rootkits. BUT, this may stop it from booting if it is a rootkit. Some sites say do a repair

Pihar.b is one rootkit by the looks of it, that infects the MBR

If you can still get into Vista I would put trojan remover on it if it installs, update then click on scan. See if it picks anything up

20-05-2014, 09:42 AM
Thanks for the replies, guys. Yes, I think that MBAM could have removed too much but how do I get it to restore from quarantine (the files are there) if the system won't boot?

20-05-2014, 10:20 AM
Have you tried running system restore from the Vista DVD ? Thats of course as long as restore wasn't disabled :p if it boots after that,of course the infections will still be there but at least it will be starting again.


20-05-2014, 10:26 AM
Yes, tried System Restore but it says no restore points on this machine. Grrrrrrrr.

Speedy Gonzales
20-05-2014, 10:36 AM
Try a bootable AV iso. Other than that it maybe a repair or a reinstall

20-05-2014, 10:37 AM
"What about "Repair" Windows option retaining files?

20-05-2014, 10:43 AM
Have done that repair option several times but still get the stop 7b at restart.

20-05-2014, 11:11 AM
Always try Kaspersky Rescue Disk 10 to see if you can effect any change to your settings/scan


Speedy Gonzales
20-05-2014, 11:14 AM
Guess its a reinstall then. You've tried everything else. Or try this (http://www.eset.com/int/download/utilities/detail/family/239/)

20-05-2014, 12:04 PM
It's looking pretty desperate. I have re-created the bootloader (lots of DOS commands) but still same result. Maybe a registry entry missing or essential file missing or something pointing to the wrong thing.

Just wish there were Restore Points or a way of getting MBAM running so it could undo its actions.

Speedy Gonzales
20-05-2014, 12:13 PM
Like we said either try an AV bootable ISO or you'll have to reformat / reinstall

20-05-2014, 02:52 PM
I've tried the eset AV ISO but only one leftover from the MBAM cleanup (PUP file in Appdata area).

I've reviewed the MBAM log and can't see how any of the deletions could have upset the boot process.

Managed to get a utility that showed a restore point to day before yesterday. I restored it and no change. Re-checked boot setup - still no change.

Put this disk in another box - stop 7B again.

I give up. First time I have had to re-install so am a bit peeved!

Thanks for the advice guys - appreciated as always.

Speedy Gonzales
20-05-2014, 03:24 PM
You could try changing AHCI to IDE in the BIOS. Whatever it was or is may have screwed the sata drivers up

21-05-2014, 10:39 AM
Not the drivers, Speedy. Did same stop 7B thing on another comp. And I did find an old image file (2010) so applied that. That image booted fine.

I now think it MAY have been a rootkit issue but I'll never know.

Thanks for your help.

Speedy Gonzales
21-05-2014, 10:46 AM
Thats the main thing, its working again. Depending on how it got infected in the 1st place, I would avoid dodgy sites or downloading dodgy files

21-05-2014, 02:03 PM
Not mine so someone else has to stop their kids using dodgy sites!!!

But who would think I would go for the dodgy stuff???

The tragedy is that even mature and sensible people, not really given to the dark side, still manage to get these things.

Speedy Gonzales
21-05-2014, 02:10 PM
Most people inc adults install programs that install malware / pups etc. Because they don't have a clue what they're installing (like 3rd party programs - they don't read the fine print, when they install whatever).

They go to the wrong sites (like download.com and cnet, which have installers full of crap). 2 sites EVERYONE should avoid like the plague

But they'll find out later when their computer plays up. And when it crashes.I know a lot of people, no matter HOW MANY times you tell them not to do this and that, they'll do it again lol

Altho it doesnt worry me, because if I fix it they'll have to pay me to fix it lol