Downloaded The Firefox 56.0.2 Final From Majorgeeks. After Install Firefox Was Dead.

Tried to reinstall v 56.0.1. It was dead too. Looked in Firefox dir and there was no Firefox.exe file.
Rebooted in safe mode and reinstalled 56.0.1.... it worked. Very strange. Anyone else see this?

 

You haven't give the normal information always required here:
What is your exact Operating System (Windows Vista, 7,8,10 and 32 or 64 bit)?
What made you think Firefox was 'dead' - describe clearly what happened
Did you search 'c/program files' and 'c/program files (x86)' for a folder in the name of MOZILLA Firefox?
Did you end up successfully installing Firefox 64 bit or 32bit? It will tell you that in 'Firefox > Help > About Firefox'

 

Sometimes antivirus, and other programs will stop a program installing- But when in safe mode the offending program is not working, and you will often see advice to install in safe mode, when that could happen (but not always)