Windows 7 - Crash trying to launch elevated command prompt

Needed to launch an elevated command prompt and now, explorer crashes when I do so.

What I've already done:
1) Run sfc /scdannow both from inside Windows 7 and from DVD. Finds files it can't fix. Appear to be due to (1) login screen customization, and (2) Vista basic custom there. But -- these have been true from when I first installed Windows 7 and have only run into this problem recently.
2) Read the thread on diagnosing Explorer crashes, applied the registry fix, generated the dump file. So, I can upload that here.
3) Do regular full-partition images, so went back three months, restoring one at time -- problem remains with the oldest restore I have -- December of last year.
4) Restored latest backup (2/25/11), ran startup repair (from DVD) three times. Rebooted Windows 7, tried elevated command prompt -- still crashes Explorer.

So, apart from a complete clean-install (which I am dreading because of all the pain I went through scrounging drivers for this XP-era Tablet PC), is there anything else I can do?

1 - start scrounging drivers "just in case". Save them to a flash drive or DVD

2 - upload the dump file. If it's too big to upload, upload it to a free file-hosting service and post the link here.

3 - check the CBS.log file (C:\Windows\logs\CBS\CBS.log) for the missing/corrupt files. Here's a KB article on it for Vista (Windows 7 should be similar): How to analyze the log file entries that the Microsoft Windows Resource Checker (SFC.exe) program generates in Windows Vista

4 - scan for viruses, scan for rootkits

5 - try a Repair Install of Windows 7: Repair Install

Already started, thanks.

Don't know how to upload files here. Is there a tutorial on that?

Catch-22 here in that, in order to do this, I have to open an elevated command prompt -- which I can't do because it crashes. Tried this from a regular command prompt and, as expected, it fails to open the CBS log file.

Did that -- nothing found

Will try this -- but need to finish collecting the drivers first. Did this on my home PC last weekend and had to reinstall and reconfigure lost of stuff. The "Repair Install" did more damage than I had expected.

But ... many thanks for the feedback.

How to upload dump files: http://www.sevenforums.com/tutorials...en-forums.html

Copy CBS.log to your Desktop, try taking ownership of it there, then see if you can open it normally. If not, zip it up and upload it (if it's too big, upload it to a free file-hosting service and post a link here).

Frankly, I don't do repair installs on Vista or Windows 7 - it's just not worth my time. At work we just backup the data, wipe the hard drive with DBAN (we have a license), and then reinstall Windows. My home system is a bit more complicated (since I test stuff on it), but I either restore an image that I made - or I do the above procedure on my own stuff.

Sorry ... been busy and not able to get back to this until last weekend.

Able to borrow a Windows 7 DVD with SP1 and did a Repair Install. Didn't fix the problem. Still not able to launch an elevated command prompt without crashing Windows Explorer.

So ... a complete reinstall is my only option at this point?

Since I now have a Windows 7 DVD (with SP1) DVD on loan, can I reinstall using that and my original product key? Or are the product keys SP-specific? I'm asking because I don't want to do a complete reinstall, then upgrade again to SP1 -- and discover it's the SP1 upgrade that breaks the elevated command prompt -- putting me right back into the situation I'm in now.

SP1 doesn't break the system - rather it's either an incompatible driver/program or malware that breaks it when confronted with SP1.

In general (no warranty is expressed or implied! ) if you can do a repair install with the DVD, then you should be able to use the SP1 DVD to do an install. Worst case is that the install will fail - in which case you can install the DVD w/o SP1 (then update drivers, then try installing SP1).

usasma: Thanks for the quick response.

I actually expected to have to reactivate with the Repair Install -- but I did not.

Since a clean install is going to take a while, especially reinstalling all the apps and customizations, I won't be able to get around to that until this weekend. But I'll post back here when I get some results.

Actually, SP1 DOES break the system -- at least, that's what I discovered when I spent the weekend reinstalling my Tablet PC from scratch.

Reinstalled from my original non-SP1 DVD, applied all the Windows updates except SP1. Rebooted (numerous times), everything was OK.

Applied the SP1 update (through Windows Update) -- machine bluescreens upon reboot.

Tried this twice (restored from image backup prior to SP1) -- and it did the same thing both times!

So, wiped the partition, reinstalled from scratch (again!). This time, downloaded the SP1 update from MS and saved it locally. Ran the SP1 update. Completed like before.

But this time, upon reboot, worked OK. No blue screen.

And, yes, this is the same set of apps and drivers as before.

So, it looks like the downloaded SP1 update behaves better than the one through Windows Update.