When try to update receive counterfeit software message.

I just was alerted that there were some updates for adobe so I clicked on the installer (aam) and it was trying to initialize an install. Then it stops half way and asks should I allow the program to take over machine and I as usual would say yes. It then says the program is counterfeit and closes (aam). Now it repeatedly does this and I cannot access even my programs installed or if I wanted to download another. ????