Issues converting certified multiple PDF's into single PDF using PDF portfolio

[Jeff32139541hifw]

Any advice on using PDF portfolio to convert multiple single certified PDF's into single PDF portfolio?

I have been doing this successfully for years, and  over past 6 months with new Imac and Macbook Air, I cannot perform this simple function.

Cant tell if account is corrupted or settings are incorrect.

Any help is appreciated.

[try67]

What exactly happens when you attempt to do it?

[Jeff32139541hifw]

it basically says the files I am trying to convert cannot be done, see below 

[try67]

Are you sure you have the Portfolio option selected? Check the Options dialog in that window.

[Jeff32139541hifw]

Yes it is.  That's why i find this so frustrating as it was never an issue before, just seems to be happemong in past few months.

[try67]

That is strange... Try narrowing down the issue. Merge two files and see if it works.

If not, try merging non-certified files and see if that works.

Also, I recommend disabling the new Acrobat UI, and to run a Repair Installation from the Help menu.