I have a student who is unable to sign a pdf document with features extended for Adobe Reader. Nothing happens when she clicks on the signature field. I open the document and I have no issues signing it. The student says she has the most recent version of Adobe Reader. Does anyone know what might cause this issue?
What you're describing is what happens when the form has not been Reader-enabled, or the extended features are no longer valid. It's hard to say what's wrong without seeing the same document that she's using. It's also possible that even though she says she has the latest version of Reader, that she's actually using something else to view the PDF, such as Preview on the Mac, the built-in PDF viewer with Firefox or Chrome, or something else.
To expand on what George already said, you need to use Acrobat Pro or a LiveCycle server to Reader Enable the PDF file. If you are using Acrobat Standard, although you can Reader Enable the file you cannot add the digital signature right. Only Acrobat Pro adds that right.