Windows 7 - Hang/crash during logon

Hi, new to the forum, and have a series of problems contributing to an awful mess, hope you can help and thanks in advance. I'll try to provide as much possible information to help diagnose what's going on here. I've tried a lot of things already, I just cant decide what to do next. Anyway, here goes:

I was using my computer, a custom one I built awhile ago(core2 duo 8800, 4GB RAM, nVidia 240, 500W PSU, and a 30GB OS SSD), running Windows 7 Pro 32 bit, when some of my programs started crashing, mostly explorer.exe, but it would restart itself and then run fine for awhile. It got progressively worse, I ran a update and scan with MSE, and it all came up green. Then I rebooted, and that was the last time I saw my desktop.

It booted back up, and prompted me to run a chkdsk, so I let it run, it scanned my OS drive, and found a lot of file errors which it claims to have fixed, then it rebooted, and came up to the logon screen, I clicked my user name, put in my password, and then it loaded to a black screen with only a mouse cursor, and seems happy to stay here doing nothing for as long as I will let it (20 minutes at least).

I can launch Task Manager, there doesn't appear to be anything running that is not supposed to, and the CPU and Disk are both basically idle. I can start a new task, launch explorer.exe, and it immediately crashes, then restarts, then crashes and never comes back unless I launch it again.

I've tried booting to safe mode to look for restore points, but it still asks me to log on, and when I do, I get the same forever black screen and mouse cursor.

I was able to get to safe mode with command prompt, and I created a new local admin user account, rebooted and tried to log in as that account, with the same results in both normal and safe mode.

So, is there anything I can try with the limited functionality of task manager and a command prompt to resolve whatever conflict/problem is causing my desktop to not load fully? I haven't had much experience with Windows 7 problems, but I'm pretty comfortable on a command line, I just dont know where to start in this case.

Thanks again for taking the time to read this, I hope we can all figure this out together!

I remember I had this exact same problem back with Windows Vista Ultimate x32. The only thing that worked for me was to install a new installation of Windows on the same drive, and then copy all the files in the *.old folders back to the installation folders. For some reason it worked even though everything still uses the same files. Wierd, I know O_o.

I posted what I did on this thread(Black Screen - Movable Cursor - Upon Boot) and also tried some of the advice there but didn't work for me. See if you can find anything that works for you. While I understand it says Windows Vista, there seem to be some similarities with your problem so checking it out is not such a bad idea.

GL!

Next time you boot into safe mode:
1. create a system repair disc. I can not overemphasize this.

2. run cmd.exe and execute:
sfc /scannow
when finished, execute EXIT
Reboot (into safe mode)
run sfc /scannow again, exiti again and reboot.

Problem gone?

I'll try sfc /scannow from the safe mode command prompt. I'm currently running the BitDefender bootable CD just to see if it picks up anything, but about halfway through and nothing so far. Thanks for the tip!

Run also Malwarebytes in Safe Mode.

Let me know the results after running sfc twice in the sequence given.

Don't get back until you've made that System Repair Disc. As yo can see, I consider that very important.

Currently cant get into GUI safe mode, only command prompt. Running sfc /scannow returned something like:

"Corrupt system files were found, some have been repaired, and some will be repaired when you reboot."

I rebooted, back into safe mode command prompt, which immediately rebooted, then I went in again, and just initiated one more sfc /scannow, so we'll see what this one says.

You may need to run repeated SFC -SCANNOW Run in Command Prompt at Boot using the System Repair Disc - Create so that it doesn't depend upon possibly corrupt System files.

Run Bitdefender CD full scan and Malwarebytes again as well to confirm you're clean.

Then run SFC again.

If you're lucky it will start, if not boot the Repair CD to run repeatedly Startup Repair,
report back results.

Startup Repair should automate System Restore but try it manually if not, as far back as you can go.

You can copy out your files using Repair CD: Copy & Paste - in Windows Recovery Console

Then borrow or download a clean copy installer for Windows 7 if you don't already have one to clean reinstall following these tips to get a perfect install: Clean Reinstall steps

The second sfc /scannow completed and reported the same thing as before, so I went back to safe mode yet again and got the same auto shutdown/reboot before I could logon, but rebooting to safe mode for a third time brings the command prompt back up for another round of sfc /scannow?

Oh, and that BitDefender scan earlier completed with no results found, so I doubt that was a problem.

I dont have my 7 discs here, and I cant see how to create any repair discs with the condition the desktop is in at this point. I'll consider this my lesson to never be without repair discs again!