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Windows 7: 0x7b - 0xC34 - Win7 Pro 32bit

15 Mar 2013   #1

Win7 Pro 32bit
0x7b - 0xC34 - Win7 Pro 32bit

Let me first start up saying that this thread comes from a not-so-shabby IT tech, namely myself, that has worked on the issue for the better part of a week, having the resources of a whole lab at his discretion.

The system in question is my machine that i built myself and that ran (including reboots) successfully for a few months. After my last uptime of about 3-4 weeks was brutally interrupted by a power outage, the computer would not boot with a: "STOP: 0x0000007B (0xC997EA50,0xC0000034,0x000etc)" BSOD during the windows logo start screen. No "INNACESSIBLE BOOT DEVICE" error as i've seen on other threads, but i feel it's the same thing anyway.

A quicklisting of my system:
Win 7 Pro 32bit kept up to date, that ran on ACHI, hosted on a Samsung 830 SSD.
MSI Z77A-GD65 with latest drivers as according to MSI's website. (i have a slight speculation that this might be a cause seeing how the drivers were quite badly labeled there)
And the rest, not like it matters since it ran with them:
I7 2700k

Let me iterate what i've done:
-Startup recovery - It actually errors on me with "StartupRepairOffline/6.1.7600.16385/Unknown/AutoFailover/29/Badpatch". Didn't go too deep into it seeing how i disabled a lot of Windows services and such.
-Safemode. Gets stuck on CLASSPNP.sys.
-Check for minidump using Bluescreenviewer in Hiren's MiniXP. Nothing gets created. This lead me to believe it really is having an issue accessing the harddrive after it loads, and seeing how it boots a lot of drivers until ClassPNP... this pointed me again to the Intel Drivers.
-I got a nbtlog to create, but given that i got there using totally unorthodox means (6months old backup sys32 thrown over), it's quite disqualified.
-For being thorough, i flashed my BIOS to date and triplechecked my BCD/fixMBR.
-Done the chkdsk etc and the SSD is in working order and uncorrupted, seemingly.
-SFC /scannow with offboot/offwindir from the RE and it said that it found corrupt files and successfully repaired them. The CBS.log didn't help me glean any useful info, but i attached it at the bottom for your perusing. I have a vague feeling running it from the RE was un-ideal. Later Edit: Nvm, ran it again and came up clean.
-I did create a fullbackup of my wininstall before i started messing around, so i have a 'clean' version.
-Various driver turn-around and tweaks ala: turn on IDE drivers(pciide), turn off AHCI (msahci plus anything with ahci in it's drivername and anything intel), which i did via Load Hive/Registry. - Nope.
-I attached a zip which contains a zip/XLS with what drivers boot up in 0/1 states, as in kernel/system boots, and the startup order.
-I also attached a zip which contains SafeMode bootuplists up until CLASSPNP.sys hang via glorious phonecamera acquisition.
-Everything that said on the first 5 pages of Google of various 7b searches.
-Spent more time on MSDN than i'd like to admit.
-Moved the whole disk over to another computer entirely and exact same error.

I let out a lot of parts since it's been a hectic week between work and fixing the same computer at work for 14 hours straight a day.

My System SpecsSystem Spec
15 Mar 2013   #2

Microsoft Community Contributor Award Recipient

Microsoft Windows 10 Pro Insider Preview 64-bit

Can you boot into safe mode with networking? Then Post it following the Blue Screen of Death (BSOD) Posting Instructions.

Follow it:
Troubleshooting Windows 7 Failure to Start

Or, run Startup Repair for three separate times, with restarts after every single run.
Startup Repair: Run three separate times.
My System SpecsSystem Spec
15 Mar 2013   #3

Win7 Pro 32bit

I appreciate the reply, but for one thing, i cannot boot into the system itself, thus, no diagnostic tool usage. Secondly, i've done the apparently "magic" three-count System Repair, and thirdly, i've marked down all of the troubleshooting guide in my second day in.

I know you get a lot of 'how do i fix computer' threads here, but i'd like a bit of credit that after a week, i've done all the basics.
My System SpecsSystem Spec

15 Mar 2013   #4

Microsoft Community Contributor Award Recipient

Microsoft Windows 10 Pro Insider Preview 64-bit

My System SpecsSystem Spec
16 Mar 2013   #5

Win7 Pro 32bit

1. If possible unplug all other HD's. Boot into BIOS setup by tapping the key given for this on first boot screen, check that Windows 7 HD is detected and set to boot first (after CD/DVD drive).
Did. Actually removed all hardware elements, and as i said before, also tossed the HDD into another system entirely hoping for another BSOD that would confirm a hardware-software mismatch issue, but came up with the same 7B.

2. Try booting into Safe Mode with Networking to install, update and run a full scan with Malwarebytes.

3. If Safe Mode is not working, download, burn to CD or write to flash stick, boot the disk and run a full scan with Windows Defender Offline. If it fails try one of these FREE Bootable AntiVirus Rescue CDs burned to CD using Windows Image Burner or ImgBurn. You can also move the HD to another PC to scan it with Malwarebytes.
Doesn't boot in any safe mode, but i did run a scan in MiniXP and it came up clean.

4. If infection cleans up enough that Windows 7 will start then run SFC -SCANNOW Command to check for damaged System files.

If not post back the virus scan results in our Security forum for expert help.
Not clean, but ran a sfc /scannow with /offboot and /offwindir in the RE. Came up with the log i attached above.

5. Once the System is clean if it won't start boot into System Recovery Options via the F8 menu or disk as shown in tutorial, run Startup Repair repeatedly up to 3 separate times with reboots in between each - no matter what it reports.
Did. No magic. Via Windows Startup Repair i get StartupRepair offline, badpatch, autofailover, with the DVD Win7 Startup Repair i randomly get could not detect a problem. Number of repair attempts: 32. Root causes: 1. Root cause found: Startup repair has tried several times but still cannot determine the cause of the problem. Sometimes i oddly get 'Boot status indicates that the OS booted successfully'. Overall. Not much help.

6. If you need an installer for your licensed version to boot to run Repairs or possible Clean Reinstall, download the latest official Win7 installer w/SP1 ISO, burn to DVD or write to flash stick using Windows 7 USB-DVD Download Tool.

7. If no installation shows up to repair when booting into DVD System Recovery Options or Repair CD, or Startup Repair won't work after several tries, click through to System Recovery Options, open a Command Line to use the Bootrec.exe tool which is demonstrated most fully in Steps 1-3 here.
It detects the installation successfully.

Failure to boot disk is almost always user error. Set disk drive first to boot in BIOS setup, look for prompt to "Press any key to boot disk." Its absence likely means the ISO or disk is bad. Alternatively tap the one-time BIOS Boot Menu key to trigger disk drive.

8. If these fail, try running System Restore from Recovery Options list working chronologically backward to find a bootable configuration. If those fail, from Recovery Options open a Command Line to run SFC -SCANNOW Run in Command Prompt at Boot.
No system restore checkpoints. As mentioned above, SFC /scannow /offboot /offwindir was done and the log in the original post.

9. As a last resort boot free Partition Wizard bootable CD to Explore C to see if your files are intact and post back a camera snap of drive map for more help. Make sure C or the 100mb System Reserved partition (preferred) is marked Active, then click on HD to highlight it, from Disk tab select Rebuild MBR, Apply. How to Set Active/Inactive partition -Partition Wizard Video Help.
Partition Wizard Rebuild MBR - Video Help.

If Windows 7 doesn't start and you restored Active flag, run Startup Repair 3 Separate Times. If marking 100mb Active fails to Repair x3, then mark Windows 7 partition itself Active and try above steps again. Make sure the Windows 7 HD is set first to boot in BIOS setup.

For a bootable flash stick version of Partition Wizard write it's CD ISO to stick using Universal USB Installer.

Without the Partition Wizard CD you would Mark Partition as Active (Method Two) from DVD/Repair CD System Recovery Options then run the 3 Startup Repairs.

Sometimes a deleted/missing partition can be restored by PW Partition Recovery Wizard. A failed partition which cannot be repaired using steps above can sometimes have its table restored using DiskGenius shareware.
Marked as active, in working order.

10. If these all fail you can copy out your data using your Windows 7 DVD or System Repair Disk using this method: Copy & Paste - in Windows Recovery Console, or Paragon rescue disk to recover data.

11. Then run Factory Recovery from its partition following steps you can find by googling, in the Manual on your computer maker's Support Downloads webpage or in this list of Recovery Methods, disks you made or order from computer maker's Tech Support, or follow these steps to Clean Reinstall - Factory OEM Windows 7 or Clean Install Windows 7.

If you can't boot disks, 90% of the time it's due to User failure. Set DVD drive first to boot in BIOS setup, then HDD, Save changes, exit.
How to Boot A Computer from CD or DVD - YouTube

Place DVD/CD in drive, reboot. Do you receive the prompt to "Press any key to boot disk?" If not the disk may not be burned correctly. Try ImgBurn at 4x speed. Or try tapping the key given on first boot screen for one-time BIOS boot menu to trigger disk.

Reset the BIOS to defaults after taking note of SATA controller setting: Clear CMOS - 3 Ways to Clear the CMOS - Reset BIOS. Try disk again.
I want to recover this system, thus my one-week crunch. I could have saved and reinstalled the system within the confines of 30 minutes, but i don't want to do that. Also, yes, reset bios, also flashed it to newest version.

Now do i have your confidence that i know half of what i'm doing? :)

Just to reiterate: Redid chkdsk and sfc just now, and both came up clean, without any errors.
My System SpecsSystem Spec
16 Mar 2013   #6

Microsoft Community Contributor Award Recipient

Microsoft Windows 10 Pro Insider Preview 64-bit

Do two more thing ..... A 7B BSOD causes mainly due to three reasons. A failing HDD, a failing Device Driver or a boot sector virus infection i.e. bootkit/rootkit. As it is not booting up, checking for a device driver is hard, but not impossible. And as far as the system is infected, no repair will work.
  1. Scan the system for possible virus infection.
  2. ChecK the HDD for errors.
    • Seatool for dos: SeaTools | Seagate download
    • Burn it in a blank cd. boot from the CD, click on "Accept", wait for it to finish detecting the drives, then in the upper left corner select "Basic Tests", then select "Long Test" and let it run.
Also upload a camera snap of the drive map using Partition Wizard Bootable CD.

If these fails, we will try to check for a failing device driver.

Unfortunately we dont use Hiren's as it is not legal; any version of XP is not redistributable as free. So it does not go with our forum rules.
My System SpecsSystem Spec
16 Mar 2013   #7

Win7 Pro 32bit

Doing as i'm typing this. The Seatools came up fine but the defender's taking it's sweet time. Will upload the Partition Wizard map once this finishes.

Sorry about Hiren.. didn't knew about it, will try to not use it/mention it in this thread. :)

As for the failing device driver, check my first post, i attached an xml of running services at kernel/boot since that's where it destroys itself. Didn't do a registry export since it writes out some values as hex which just muddles a clean view of the issue.

The issue is that it boots into the windows logo and i see it loading drivers in safe mode, so it reads the HDD fine, up until CLASSPNP.sys which i assume helps load some of the drivers in the store, after which it stops communicating with the drive completely, thus not even writing the minidump.

This really is a true first where i'm stumped and have close to no leads on the issue.

LE: Windows Defender came up clean aswell.
LE: Did a Surface scan@PW and that came up ok.
My System SpecsSystem Spec
16 Mar 2013   #8

Win7 Pro 32bit

My System SpecsSystem Spec
16 Mar 2013   #9

Microsoft Community Contributor Award Recipient

Microsoft Windows 10 Pro Insider Preview 64-bit

Here is it .... so that the others can see it easily.
Attachment 259571

It is a 60 GB SSD? Upgrade its firmware. As you cannot boot into windows, you can boot into Puppy Linux and update the firmware in linux version. Or you can do it otherwise you think .....

If still it does not boot even after the firmware upgrade .......

Remove the SATA and power ports from the other HDDs than the 60 GB SSD. Then try another startup repair. Does it detects a windows installation? If so, let the repair run three more times and see what happens, with the other HDDs disconnected.
My System SpecsSystem Spec
16 Mar 2013   #10

Win7 Pro 32bit

I made sure i was up to date no more than two weeks ago so that's not it. I know for sure since i was investigating some performance statistics.

As mentioned, i tried a full disconnect in the same system with just the SSD and did the pseudomagic 3x startup repair, same thing (various StartupRepair Offline/No problems found/System booted succesfully), and i also tried tossing it in another system altogether, hoping for a different BSOD, and i still get that 7B.
My System SpecsSystem Spec

 0x7b - 0xC34 - Win7 Pro 32bit

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