"Access Denied" when trying to sign in

[Gamer5FAC]

This pop up appears whenever I start Adobe Reader, which is very annoying to have to close everytime I use a PDF. Adobe Reader still works fine, but I am unable to sign in at all. Clicking on "sign in" takes me to a sign-in screen, but after I put in my information and log in, the pop up just closes with no change to my sign-in status. 

[Gamer5FAC]

Note: this is a personal computer, so I am not sure what the "IT administrator" is referring to.