Two alternatives using Acrobat DC assuming that you don't have the original source document: (FWIW, it is always best to go back to the original source document, edit that, and regenerate PDF.)
- Use the edit function of Acrobat DC to add/edit text. Note that this works best for relatively short text additions / edits.
- Assuming the content of the PDF file isn't overly complex, export to Word from Acrobat DC, add / edit in Word, and create new PDF.
If it were that easy to go to the original source document, i would not be asking the question. It is not available.
Also the file is complex. Not able to copy/export to Word.
"edit function"? How/where do I find this?
I see "Edit" as a menu choice, but then what?
In Acrobat DC, click on the Edit tool after you have opened your PDF file. That provides a set of tools for editing and also puts frames around text selections. One of those tools is Add Text. For existing text, simply move your cursor within one of those text frames and edit with the keyboard (including adding, deleting, and replacing text). For new text, click the Add Text option, move the cursor to where you wish to add text, and click — at that point you simply type the text you want/need.
It turns out I have Acrobat X, not DC. The options you mention are not available to me.
I did ask about upgrading, but the Adobe people said I could have these functions with Acrobat X and said I had to ask the forums.
Look under Tools - Content Editing - Add Text. You can also use the Add Text Comment tool under the Comment panel.