Where do you have that file and how you have been trying to open it?
Using the Acrobat Reader mobile app or working on the Adobe Reader desktop application?
If on system, then right click on the file>Document properties>Security>Check permissions.
This message generally appears when you do not have Read permission to the document. Try opening another file and see if that works.
Acrobat Reader 17.06.12 is now available in the App Store.
It should resolve the problem that you have experienced.
Please give it a try and let us know if it works for you.
We apologize for the inconvenience this may have caused.