Windows 7 Forums
Welcome to Windows 7 Forums. Our forum is dedicated to helping you find support and solutions for any problems regarding your Windows 7 PC be it Dell, HP, Acer, Asus or a custom build. We also provide an extensive Windows 7 tutorial section that covers a wide range of tips and tricks.

Windows 7: Can't reboot repair or restore aft aborted Avast uninstall Oxc 000000f

01 Jun 2015   #1

Windows 7 Home Premium
Can't reboot repair or restore aft aborted Avast uninstall Oxc 000000f

I was having problems with Avast free edition. It was detecting a problem when doing a root scan but wouldn't allow me to see the results. After doing a search, it appeared that I just had a corrupt Avast install and it was recommended that I uninstall it via the control panel, reboot in safe mode and run their second uninstall program that's supposed to make sure everything is removed, and then reinstall Avast. The uninstall proceeded to where the progress bar appeared to show it was complete but it seemed stuck on finishing the final step so I foolishly did a forced reboot. I assumed that anything that was missed would be taken care of with the second uninstall program.

Unfortunately, the system will not reboot. Win 7 Home Premium gives error Oxc 000000f Boot Selection Failed Required Device Inaccessible. When I tried to reboot in Safe mode, I'm instructed to insert my Install DVD and run a repair. I did but the repair wouldn't work. I tried to do a System Restore from the System Recovery Options but it says no restore points exist.

Looking at the logs from the attempted Startup Repair, I see, "Root cause found: Boot critical file D:\Windows\system32\drivers\ACPI.sys is corrupt. Also,
Repair Action: File Repair
Result: Failed. Error Code = 0x2
Time taken: 4181ms

Repair Action: System files integrity check and repair
Result: Failed. Error Code = 0x2
Time taken: 3354 ms

Is there anything I can do besides a clean install? I've got a lot of software and don't want to have to spend a couple of days restoring this machine, if possible.

Any help will be greatly appreciated.


My System SpecsSystem Spec
01 Jun 2015   #2


Everything possible to start Win7 is here for Troubleshooting Windows 7 Failure to Start.

We see nothing but trouble with Avast any more since it bloated up and causes problems.

This time if you reinstall follow the steps in Clean Reinstall Windows 7 to get and keep a perfect install backed up in a System Image you can restore in 20 minutes if Restore Points fail.
My System SpecsSystem Spec
01 Jun 2015   #3

Windows 7 Home Premium

1. Via the F8 Advanced Boot Options menu, choose the "Last Known Good Configuration" option to attempt to return the machine to a working state. This is a quick operation that is often useful when non-booting is due to a recent system change.

This just sends the computer into install mode. When choosing repair, the message comes up, "Startup Repair cannot repair this computer automatically."

2. Boot into System Recovery Options via the F8 Advanced Boot Options menu or disk as shown in blue link tutorial, open a Command Line to run a full Disk Check (chkdsk /f) on both the System partition and Windows partition (if they're not one and the same).

Scan completed and I see, "Windows has checked the file system and found no problems." But the final line says, "Failed to transfer logged messages to the event log with status 50." I'm not positive what that means but one of the issues Avast was having was showing a problem detected during a scan but clicking on the "Show Results" button didn't work. Checking Avast's logs said no virus found. Maybe no relation to this issue but I thought I'd point it out.

3. The BIOS detects the Windows drive. I also removed another drive from the system so there would be no confusion over which to boot.

4. Startup repairs have failed multiple times. Chkdsk results the same as in step 2. But I don't know how to isolate the System partition and Win 7 partition and that wasn't covered in the linked page.

5. The Bootrec commands in the startup prompt all completed successfully. However, rebooting lead me right back to the original Windows failed to start error.

6. Next, I ran all the commands in Bootrec.exe tool. THey executed successfully but the reboot produced the same old 'failed to start' error.

7. I cannot boot the system into Safe Mode. Same Boot Manager error as before.

8. I believe we already know the reason for the computer not starting, my premature reboot while uninstalling avast.

Honestly steps 9 on are a bit too technical for me. I'm reading the suggested pages but there are assumptions that we know, for example, what an MBR install is as well as some of the language about reserved partitions. I'm typing this on an Asus laptop with no CD/DVD drive and the flash boot drive doesn't make a lot of sense to me.

I understand that forums like these want everyone to try the standard list of repairs to attempt fixes and provide details. I'm hoping that in this case, since I know the exact cause of the problem and have already mentioned above the file that's either missing or corrupted that there might be some other way to recover it. If not, I guess I'm going with a clean install. Hopefully someone has seen this before and knows a fix.
My System SpecsSystem Spec

01 Jun 2015   #4


The boot files are corrupt. There are multiple ways to try to repair them all of which are dealt with in the tutorial.

Did you export and then Rebuild the BCD following Bootrec.exe Tool - How to Use in Windows Recovery Environment - Windows 7 Help Forums?

If we could see a picture of Partition Wizard boot CD output we might be able to spot the problem directly. We need to know for sure which partition is marked Active. There are other repairs given that PW can also perform in Step 9.

Manually this can be determined by following he prompts in Mark Partition Active Option Two Steps 1-5 but instead of typing Active in Step 6, type Detail for each partition to see which one lists in its details that it is Active. It should be either the 100mb System Partition or Win7 partition. If not try marking each of those Active to run Startup Repair - Run 3 Separate Times to see if you can either activate the boot files on that partition or move them to the other partition.

Finally there is Step 10 which almost always works for me when all others fail: to create, or delete and then recreate, the System Reserved partition and let the installer rewrite the boot files to it and make it bootable. This wipes out the corrupt file(s) to replace with a new set of boot files and makes them bootable.

If you need further help I can walk you through these steps as needed. If you want to know you've tried everything you can go on to Step 11 if 9 and 10 don't work and seek help for that one from its expert paul1149

And of course you can always skip to rescuiing your files and then doing a perfect Clean Reinstall Windows 7 which if followed closely always results in a perfect install which will stay that way for as long as you stick with the tools and methods suggested.
My System SpecsSystem Spec
01 Jun 2015   #5

Windows 7 Home Premium

Thanks for the quick response!

Quote   Quote: Originally Posted by gregrocker View Post
The boot files are corrupt. There are multiple ways to try to repair them all of which are dealt with in the tutorial.

Did you export and then Rebuild the BCD following Bootrec.exe Tool - How to Use in Windows Recovery Environment - Windows 7 Help Forums?
Yes, the commands executed and found one install of Windows. However, I still get the same Failed to Start Error.

Quote   Quote: Originally Posted by gregrocker View Post
If we could see a picture of Partition Wizard boot CD output we might be able to spot the problem directly. We need to know for sure which partition is marked Active. There are other repairs given that PW can also perform in Step 9.
The challenge with the Boot CD solution is my laptop doesn't have a a CD or DVD drive. I'll see what I can do about getting on another machine.
My System SpecsSystem Spec
01 Jun 2015   #7

Windows 7 Home Premium

Thanks, Greg. I downloaded the partition wizard software but see nothing there that shows me how to create a bootable CD. Instead, it directs me to download a MiniTool Partition Wizard. The instructions say...

To see a picture of your drive map with listings, boot free Partition Wizard bootable CD or flash stick to Explore C to see if your files are intact and post back a camera snap of drive map here for more help since often the problem is obvious to us. Screenshots and Files - Upload and Post in Seven Forums - Windows 7 Forums

Make sure in a normal MBR install that the 100mb System Reserved partition (preferred if you have it) or Win7 partition (if you don't) is marked Active: How to Set Active/Inactive partition -Partition Wizard Video Help. A UEFI install will have an EFI System partition on a GPT formatted disk and no Active flag.

For MBR install, click on Disk # to highlight it, from Disk tab select Rebuild MBR, then Apply: Partition Wizard Rebuild MBR - Video Help.

If Windows 7 doesn't start run Startup Repair 3 Separate Times. If marking 100mb Active fails to Repair x3, then mark Win7 partition itself Active and try above steps again.

Without the Partition Wizard CD you would Mark Partition 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.
Yet, there's very little on how to actually do that, especially if you don't know the terminology. I had to Google MBR to know it means Master Boot Record but still, I'm not even sure if that's what I'm doing. 'marking 100b Active' Not sure what how to do that at all.

What I do know how to do is to reinstall Windows 7. It's going to take 2 days with all the updates and finding and reinstalling programs but at least I know exactly what I'm doing.

Thanks for your help and, can I ask, what AV program do you recommend to replace Avast?
My System SpecsSystem Spec
01 Jun 2015   #8


I'll try to reword the step to explain that you Download the Partition Wizard CD version for Win7 then burn to CD using WIndows Image Burner which is built into Win7. If you want to use a flash stick I posted the illustrated steps for that above.

The difference between an MBR and EFI install is explained in Step 2, particularly where it explains how to discern if you have an EFI install. I'm not sure how that could be explained better but if you have a suggestion then it may help others understand it better too.

The blue links which did not come through in your quote above are illustrated tutorials showing how to perform steps. You can always ask for help in the tutorial comments or your own thread.

Everything that works best for Win7 is compiled in Clean Reinstall Windows 7. If you have a question for any or all steps, feel free to ask back here or in the tutorial comments section for quick response.
My System SpecsSystem Spec
01 Jun 2015   #9

Windows 7 Home Premium

I've got so much on this computer that it will take a week to reinstall everything so I'm trying it your way. :-)

Right now, I've managed to get the MiniTool Partition Wizard onto a disc and booted up on my problem PC. I'm going to assume by 'camera snap' you mean literally take a photo and there's no capture function in the MiniTool. See the attachment.

From looking at the screen, Disk1 has a 100mb partition C and the rest of the drive is D although it doesn't show the letters here. Disk 2 is a backup USB drive I attached to try to backup some files.

I'll keep working on the other steps. Let me know if anything jumps out regarding the camera shot.

Regarding wording the docs more clearly...

One thing that was confusing initially is the partition wizard software suggestion. The 12 step document refers to download free Partition Wizard bootable CD but there is a similarly named free program up top and you have to scroll down the page to download the right software. Sounds obvious but when you're jumping through a lot of hoops, it's easy to miss.

Also, the 12 steps are a bit jumbled. Notice there is no Step 6 and two Step 12's? Oops, but an easy fix.

Now for someone without a ton of experience following the steps and being instructed as follows...

On a Legacy install to MBR disk, confirm the Partition Marked Active is the 100mb System Reserved (preferred if you have it) or Windows 7 partition (if you don't), run Startup Repair repeatedly up to 3 separate times with reboots in between each - no matter what it reports. If both the System Active and Win7 partitions are on the same hard drive then unplug all other drives to do these repairs.

On some PC's the Recovery partition or an earlier installed OS used in a Dual Boot will hold the Active flag. If another partition than System Reserved or C holds the Active flag and you know this is how it was set up, then go ahead with the repairs. If not skip to Step 9 to get more help since Win7 will not repair unless the correct partition is Set Active. Only the System partition booting the OS should be marked Active.

A UEFI install to GPT disk must have its installation media or Repair CD booted as a UEFI device. A UEFI install has a EFI System partition instead of System Reserved, and a (hidden) MSR partition, can only boot from a GPT disk. Confirm using Diskpart commands or free Partition Wizard CD that these partitions are intact and run Disk Check on all of them including Win7 partition. Then from System Recovery Options run Startup Repair and if necessary System Restore.
The challenge here is this. I'm no coder. Not even close. I built my current machine and have built several others. I build websites and such. But I have absolutely no idea what a Legacy Install to MBR disk means nor do I know what a UEFI install to GPT disk is. So the instructions just say what to for for each type but don't provide any clue on how to tell which you have? Perhaps linking those out to deeper definitions would help. You're saying they're in step 2 but if so, it's not obvious. You have to remember, you're knee deep in this every day. And please, I'm in no way trying to be critical. You guys kick ass. Hopefully this helps because the more problems get solved with the document, the less you have to solve them individually. Screen shots would probably help quite a bit, too. I use them a lot for my clients. Ditto for screen capture videos.

Attached Thumbnails
Can't reboot repair or restore aft aborted Avast uninstall Oxc 000000f-speedscreen.jpg  
My System SpecsSystem Spec
01 Jun 2015   #10


Why is the Seagate backup drive plugged in? All other disks are to be unplugged during repairs as stated in the tutorial.

I don't know how both System Reserved and C can be Active. Only one partition per drive should be allowed to be Active at a time. So rightclick C to Modify>Set Inactive, click OK, Apply step.

Then highlight Disk 1 label, from Disk tab select Rebuild MBR, OK, Apply.

Then boot into Win7 disk to run Startup Repair - Run 3 Separate Times .

If that fails test the hard drive with the maker's HD Diagnostic extended CD scan, or if there isn't one use the PW Surface scan from the Disk tab. There could be serious disk problems if it allows two Active partitions.

Next I'd do the Bootrec commands from tutorial again to export and RebuildBCD.

If that fails delete and recreate the 100mb System Reserved partition from Step 10 in Troubleshooting Windows 7 Failure to Start
My System SpecsSystem Spec

 Can't reboot repair or restore aft aborted Avast uninstall Oxc 000000f

Thread Tools

Similar help and support threads
Thread Forum
Avast - Uninstall Completely
How to Completely Uninstall Avast Antivirus This tutorial will guide you through removing Avast products completely from your machine, either so you may reinstall it or make sure everything is cleaned up to move to a new anti-virus. This guide assumes you have no antivirus protection...
Uninstall Avast Free Antivirus
Am using a HP Probook 4540s, running on A Win 7 x64 bit OS, 4gb ram, 2.6ghz core i5, I installed Avast Free Antivirus and it reached a point whereby it wouldn't update but lags a lot, I tried uninstalling it normally with windows uninstall program but it wouldn't go through, tried Revo uninstaller...
System Security
Windows 7 system repair loop after AVAST uninstall
Hello, This is my first post to any forum ever so please bare with me. This is my problem, I uninstalled avast antivirus on a toshiba laptop and now I'm stuck in the infinite windows system repair loop. I have tried to fix windows boot with a windows 7 installation cd using bootrec with no...
Backup and Restore
Uninstall Avast!
Windows 7. Whilst installing a one-year Kaspersky Internet Security disc I was warned that I should uninstall (free) Avast. Avast does not appear in the list of programmes available for uninstallation. How can I either turn it off or move it onto the 'Uninstall' list? Thanks for any help.
System Security
Cant repair an aborted windows 7 install
Hello, I decided to give my acer aspire 5515 to my stepson, so i was reinstalling windows 7 on it and it accidently aborted before finishing installing. Now when I put my disc in it doesn't read it and never repairs it, never completes it, just keeps rebootiing. I have tried set up default...
Installation & Setup

Our Sites

Site Links

About Us

Find Us

Windows 7 Forums is an independent web site and has not been authorized, sponsored, or otherwise approved by Microsoft Corporation. "Windows 7" and related materials are trademarks of Microsoft Corp.

Designer Media Ltd

All times are GMT -5. The time now is 19:41.
Twitter Facebook Google+ Seven Forums iOS App Seven Forums Android App