Adobe reader DC: unsupported file
I have adobe reader DC and I use it mainly to send documents for signature. I have one document "Proposals" and that sends for signature just fine. I have another document "contract" that I get an error message: could not send unsupported file. Why can I send one and not the other?? The proposal is a normal PDF file. The Contract is a form created by one of our companies and it was created with Adobe Indesign CS3(5.0) and it is "secured" but in the permissions it is checked to be able to receive signatures.
