Why wouldn't my PDF documents open in my newly installed Adobe Acrobat DC?

[Felisa5C60]

Hi, I've disabled my antivirus software and downloaded Adobe Acrobat DC but my PDF files will not open. 

Each time I try, I get the following message:  Adobe Acrobat Reader could not open (name of file) because it is either not a supported file type or because the file has been damaged (for example, it was sent as an email attachment and wasn't correctly decoded).

I have allowed the program to communicate through my Windows Firewall and still I am unable to open my PDF files.  Can someone please tell me why that is?

Thank you.

Felisa Wash

[John T Smith]

You say Acrobat and then you say Reader... which do you have?