I have Adobe Acrobat DC Pro and am trying to edit a form by adding a text box. I usually have no trouble doing this but with this form I am getting a message that says, "This form cannot be edited in Adobe Acrobat DC. Please use Adobe LiveCycle Designer to edit this form." Why am I getting this message and is there a way around it so I don't have to purchase more software?
You are dealing with a form created in Adobe LiveCycle Designer. These are XML forms, "wrapped" in PDF. Acrobat can only fill these forms, you cannot edit them. Adding a annotations or form fields in Acrobat would be editing. That's why you are getting this message. The only way to modify this form is with LiveCycle Designer (and any application that can modify the XML in the form).