Unable to see fill and sign in features when I open a PDF

[Holly5c32]

I have used Adobe Acrobat for a couple of years marking students assessment and signing them.

For the past week or so, each time I open a PDF document, the fill and sign and all the features that are usally displayed in the right hand pane are not there.

I have the latest Adobe Acrobat DC installed on my desk top and it is apparently up to date.

Any ideas what the problem is?

[Holly5c32]

I have fixed the problem.  The PDFs had a HP Sure protection.  If you remove this protection the PDF automatically opens up as it should, with all the features displayed on the right hand pane.