Hello and welcome to the community. 
Just making sure - you added the installer as an antivirus exception before launching it? Otherwise, adding it as an exception after the antivirus already blocked it will not un-delete any critical files the antivirus deleted. If you didn’t, try downloading a fresh copy of the installer and adding it as an exception first.
If that doesn’t help, see this thread here, which contains more steps to try out: I can’t Install WeMod / "There was a error installing the application" - #2 by Ravenfyre.