Windows 7: MSE disappeared

I finally paid attention to my status bar. It told me I had anti-viruis problems. I could not fond MSE which I was using. So I tried to install new. TYhe installer told me that it was already installed. I used "Revo Uninstaller" to uininstall. The MSE installer told me there was an error but did not tel me anything else.

At this point I decides to restore an image of a week ago. MSE was still missing and I went through the same effort as above. So I restored the current image.

Now I can't install because the installer says already installed. I can't uninstall because I get an error. I'm in a quandary. Any ideas?

Incidentally the folder C:\Program Files\Microsoft Security Essentials\ is not there anymore. File Mse.exe is gone too. Why does MSE show up on Control panel ...Uninstall?

Sometimes the Uninstall programs does not remove the entries from the Control Panel's Programs and Features window. This is caused by the Uninstall programs not removing entries about these programs from Registry.

You can try the CCleaner program (a good freeware program) to clean the stray files and stray registry entries from the system. CCleaner also has a feature to remove the leftout entries from the Programs and Features window. You can remove the leftout MSE entry from teh registry using CCleaner.

After this you can install the MSE again. If you wants an alternative to MSE, you can use Comodo Internet Security Premium which is a free Antivirus and Firewall program with good reputation.

Went to Ms Support and they gve me instructions for scanning with differentAV's and trying to install. I did and got the same error messge.
Tried to install the AV you recommended, Comodo Internet Security, and got the error message 1603.That's where I am now.

Do you have Malwarebytes : Free anti-malware, anti-virus and spyware removal download installed? If not, try to download/install it, update and run a full scan. Something is causing some serious issues and I would make sure that malware wasn't responsible.

Just finished a malware full scanusing Malwarebytes. Nothing detected. I'm beginning to contemplate a clean install of Windows 7.

How about SFC /SCANNOW Command - System File Checker ?

Just did it. Found a bunch of corrupted file. Repaired them. However, installation still fails as did the Comodo AV you recommended,

As soon as I find out what folder(s) the email data is kept in I'll do a clean install. Thanks for the help.

It is a good idea to rerun the SFC/ SCANNOW command at least twice if it found problems and repaired them. I would give it another go until it finds no errors. Hopefully, it will find & fix the issue.