Can only install programs in Safe Mode or from external drive

[njride]

If I try to run most setup.exe files from Windows Explorer (including Desktop) nothing happens and the Explorer folder (or Desktop) freezes. Doesn't matter if I click normally or as an Administrator, and doesn't matter from which User Account. The behavior is not consistent among all setup.exe files, but most of them fail. I cannot discover any pattern (size, date, name, etc) for which do or don't work, but the ones that do, always do, and the ones that don't, always don't.
The only way that I've been able to consistently install programs is in Safe Mode or from a USB drive.
Here's what I've tried so far for Normal Mode, with no luck: disabled all Services and all Startup programs, trimmed all added context menu commands, system restore to a state of about one month ago, scanned for malware.
Thanks for any ideas.

 

[MarkW]

I am going to guess that after all of the things you have done manually to that system now, that you will never be able to get it back to the way it should actiually be.

As such, trying to get there manually would be like dragging a dead horse down the road in the hope that it will come back to life and take you back home.

NOW, BEFORE YOU ATTEMPT TO DO WHAT IS BELOW THIS LINE, MAKE A BACKUP OF ANY AND ALL DATA THAT YOU VALUE THAT IS ON THAT DRIVE.

So I want you to boot from the Windows Install DVD. Instead of installing windows though, I want you to repair Windows. This can take a very long time, so if it does take a long, time, you are going to need to be patient. If you reboot during that process, you are going to pretty much trash everything on that partition at a minimum. If it works, it should get your back to where things should run again. If it does not work, you are likely going to need to format the partition, and reinstall everything.

 

[reedo_43]

Smells like malware to me if it works in safe mode. Download malwarebytes and run a scan.

 

[njride]

Smells like malware to me if it works in safe mode. Download malwarebytes and run a scan.

As I mentioned at the end, I had already scanned for malware [using malwarebytes]. Did again yesterday.

 

[njride]

I am going to guess that after all of the things you have done manually to that system now, that you will never be able to get it back to the way it should actiually be.

I'm not sure what you mean by all of the things I have done. They seem to be simple diagnostics that are universally recommended. Anything I disabled I re-enabled afterwards. Also, things were never the way they actually should be; this was a Win7 to Win10 upgrade foisted on me by MS update when I left my PC unattended one night, with most of the Win10 issues that people report (missing or broken apps, quirky Start button, slow-mo operation, etc.)

So I want you to boot from the Windows Install DVD. Instead of installing windows though, I want you to repair Windows. This can take a very long time, so if it does take a long, time, you are going to need to be patient. If you reboot during that process, you are going to pretty much trash everything on that partition at a minimum. If it works, it should get your back to where things should run again.

Yeah, I already did that with the Microsoft downloaded ISO image soon after the initial upgrade to try (unsuccessfully) to fix the issues I mentioned above. Maybe it's time to try that again.