Could I download a disguised virus in a fake Firefox update? Ever since the last upgrade none of my .exe files will run. The version number of the upgrade was lower than the latest version. My computer is in real trouble!
I deleted the "upgraded" version and tried to reload the latest version from Firefox website. I could download it but could not run it. Computer asks for an application to run the file with, and there is none. Also, all of my system applications now no longer respond.
Opaite Mbohovái (1)
That does sound suspicious. You may want to run some supplemental scans. These two tools are highly regarded:
Malwarebytes Anti-malware : http://www.malwarebytes.org/products/malwarebytes_free
SUPERAntiSpyware : http://www.superantispyware.com/
If your system is clean of malware, you could completely remove all versions of Firefox and install again.
First, I strongly recommend backing up your Firefox settings for future recovery. See Backing up your information. (You can copy your entire Firefox profile folder somewhere outside of the Mozilla folder.)
Get the latest installer from http://www.mozilla.com/