Acrobat Reader cannot edit files or sign

[Multifaceted Man]

I open a new file with my Adobe Acrobat Reader application for Mac. It opens alright, however I cannot edit any of the open document spaces or sign. I have created a signature for Adobe. But, when I attempt to use it I get a warning/error for "bad parameters". I don't know how to proceed. And I need these files ASAP.  Somebody PLEASE HELP!

[Ladislav1984]

Hello I don't understand

[Multifaceted Man]

The application will not allow me to edit or sign anything I open. I am signed into the application but to no avail.

[try67]

This error message usually means the file is corrupt. Report this issue to the creator of the file.

[Multifaceted Man]

I wish you were correct, however, it is every file; from everywhere. Adobe, College, Event Coordinators, Private Contractors, etc.
No matter what document or file, I am unable to work with. I feel like I've tried everything.