Can't boot computer

[I'm really struggling to type this on my phone] (Fixed the grammar on another computer), basic info:
I can't boot my computer in normal mode or safe mode. When I try to do so, after the "starting windows" page the only things that come up are my mouse, a black screen/background, and a "logonui.exe-bad image- Authui.dll isn't designed to run on windows" error/message (not the exact message). I can't use a system restore (it can't find a restore point), the image recovery tool finds no image to restore from, system repair either doesn't find a problem or can't fix the problem, and basically nothing else works (none of the advanced boot options or other various buttons and tools do anything noticeable). I've even tried to use sfc in command prompt, but whenever I do any sfc things at all (/scannow, verifyonly, verifyfile, etc.) it says there is a system repair pending that requires a reboot. I've restarted 7-8 times and the exact same message keeps coming up. I'm looking for any general help I can get right now, [I can post my computer specifics in an hour when I have time](posted a few). I have an HP pavilion dv6-6135dx wiht Windows 7 x64.
Edit: not sure what info is helpful, but here is some:
Processor: AMD a8-3500m APU, raedon graphics
bios vender/version: insyde, f. 20
I'm having trouble getting more info because my computer is still crashing occasionally and I don't really know what else is relevant; if you need more, I might need directions on how to get it. Especially if it involves command prompt.

I should also add that it has been crashing more often than I think is normal ever since I got it, but recently it BSODed 3-4 times a day. I have antivirus and also ran a full malwarebytes scan yesterday, and it only found one little issue which was resolved.

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Essential Member
Microsoft Community Contributor

You can try this...

Restart your computer

Repeatedly tapF8 on your keyboard

When the "Choose an option" screen appears, click Troubleshoot

Click Advanced options

Click Automatic repair

Select an administrator account

Enter the password for that account

Hit start, or whatever is asks for.

If that doesn't work, you may have to do a repair install from you Windows disk.

Repair Install - Windows 7 Forums

If you have service pack 1 installed and your disk doesn't have service pack one on it you can download an .iso file for Windows 7 with Service Pack 1.

Make sure that it is the same version of Windows that you are running.

Official Windows 7 SP1 ISO Image Downloads

You will have to make the disk using a program that burns .iso files and makes a bootable disk.

I use Imageburn, it's a free download.

The Official ImgBurn Website

I see a number of people with this problem but not a lot of solutions except reinstalling.



Excellent Member
Microsoft Community Contributor
If you system has been crashing, did you set it to get a dump file? If you can access the drive, you might look in the
C:\Windows\Minidump folder to see if a .dmp file is there..Attach it using the paperclip on Advanced Replies if you find one.

Sounds like something has gotten corrupted, and whether it is your memory, or drive, or even processor, hard to tell.

How old is the system?

It sounds like it is getting to the LogonUI, which comes almost last in the boot process, so maybe your C: partition is corrupted. Perhaps a Chkdsk might help, and if you can run a System File Check, you might try running it offline as per the link. Not sure it will work if you don't see an install on the system. But if you can get to a command prompt, you can try it. Just make sure what drive letter is you Windows 7 install. It may not be C: in the command prompt window.

Link Removed - Invalid URL

The directions from the first response don't quite match up with my options on the f8 screen- I have things like repair your computer, safe mode options, and some more advanced things like enable boot logging and directory services restore mode (most of which I've already tried.) in response to the second poster, the computer is just over a year old, and I've tried the system file checker many times in many different ways, and it always immediately comes back with a message that there are fixes pending that require a reboot. In reality, there aren't and it doesn't. I definitely think at least one important file got corrupted somehow, probably a number of them.

I'm currently in touch with one of my tech savvy friends, so I'll see if he can't at least help me get the files off so I can reinstall the core files without losing too much data.

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Joe S

Excellent Member
If you can get a Linux Live CD and boot from that you may be able to get the dump file if the system won't boot. You can also use it to recover or copy data sometimes.


Essential Member
Microsoft Community Contributor

I use Ubuntu it seems to work on almost everything.

Download | Ubuntu

You don't have to install it, it will run from the disk.

If you can do a repair install you shouldn't lose anything or have to re-install anything.

I would still back up everything important first anyway, you never know what's going on for sure.

When you get everything up and running make a system image to restore from next time.


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My friend also suggested using a Linux or even Mac os to access the files. However he couldn't help me at that moment, so I played around with it for a while. After doing some research and being frustrated, I just deleted the authui.dll file. Which caused the mouse and keyboard to stop working. Ended up doing a hard reset, if that's what it's called, after which the keyboard and mouse worked again and I managed to boot it in safe mode with command prompt. Long story short, after a few BSODs I got it to start up and login normally. I'm currently doing a chkdsk and making a backup- never mind, it just blue screened as I was typing this. So much for that, I'll see if I can get it up again in safe mode again.

One thing I noticed was that my wireless doesn't work at all, so not all of my drivers are fixed yet. Assuming I get it up in safe mode (or normally) again, what steps should I take to fix all this crashing and make sure all my drivers and such work as they should again? I should note that the only helpful media that I can find are some recovery disks (that I didn't make.)

Thanks for all the help and suggestions so far.

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Essential Member
Microsoft Community Contributor
If you can get it back into safe mode it might be a good idea to back up anything you really don't want to use, i.e. photos, music, job files what ever before you do anything else.

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