Everything Microsoft related is crashing

So I've been having this really strange and annoying problem where numerous programs crash immediately after I start them, and so far, all of them have been made by Microsoft. So far the list is up to Windows Explorer, Gadgets, Internet Explorer, Word, Powerpoint, Publisher, Windows Media Player and System Maintenance. In addition (I don't know if it's related) I can't install certain programs like Avast! Antivirus or CCleaner. I've run a virus scan with Avira and it didn't find anything and I did a system restore back to the furthest point I could and nothing happened. Another thing is that my Gadgets work, but only if I use the ones that came with Windows. I can't use any of the one's I downloaded after the fact. The only thing I can think of is at one point I had AVG 11 and updated it, which cause the endless loop startup crash, but I was able to fix that. I'm just not sure if that cause additional problems in some files somewhere. If anyone has any idea why this is happening it would be very helpful! Thanks!

I submitted a thread on the microsoft forums but nobody is on those, here's the link:
Everything Microsoft related is crashing

You mention AVG and Avira. Both have caused issues in one way or another with Windows 7.
I take it you now only have the one installed. I'd be tempted to uninstall the present set up, run the AVG and Avira AV Uninstallers, preferably in safe mode, to clear up any remnants. Then install Microsoft Security Essentials and see if I was still getting the same problems.

In addition (I don't know if it's related) I can't install certain programs like Avast! Antivirus or CCleaner

I'd also download and install Malwarebytes, update, run a scan.

So I uninstalled the software you told me to, but when I went to download the Microsoft Security Essentials the installer crashed just like all my other Microsoft related products are doing. I also ran Malwarebytes and it found nothing.

Hi,

Silly question but is your windows 7 and office legit?

Basher

Does sound odd.

If you'd said you couldn't download / install Malwarebytes I'd have immediately suspected a virus / trojan.

Yeah, both my windows 7 and office are legit. As for Malwarebytes, I already had it on the computer so I didn't need to download it.

Hmmm intresting one...

DEP setting setting might cause the programs to crash. To check those settings
1. Click on Start and Right Click on Computer and go to Properties
2. The click on Advance system settings.

3. There click on Advance Tab and click on Settings under Performance session.

4. Click on Data Execution Prevention.

5. Make sure you have selected “Turn on DEP for essential Windows programs and services only”
6. Then click Apply and click OK and reboot your system

Captain Jack, I tried what you suggested by my settings were already on "Turn on DEP for essential Windows programs and services only".

Hello,

Run SFC /SCANNOW Command - System File Checker - Windows 7 Forums