I have several PDF files sent to me by others. I need to sign and send back, however, the Sign Document options in the menu are grayed out, they are unavailable. How do I gain access to sign these documents?
As per the description above, you are not able to use the Fill and Sign feature as it's greyed out, Is that correct?
Please make sure that you are logged in with your Adobe ID and password in Acrobat or Reader installed.
You can also Sign the PDF through your online account: https://cloud.acrobat.com/fillsign
Also, refer to the following link which discusses the similar issue: I want to sign a document in Acrobat, but the option is grayed out. (Protect PDF) Link: https://answers.acrobatusers.com/I-sign-document-Acrobat-option-grayed-out-q3161.aspx
Hope this helps, and keep us posted with the results.