MOVED TO THE ACROBAT READER FORUM
Hope you are doing well.
As mentioned that you are getting a blank save as box. Here is discussion link for the similar issue, kindly follow the troubleshooting steps provided there.
Let us know if that helps.
Also what about digitaly sign pdf files. Some times signature is showing and or not
Sorry for the delayed response. kindly check this discussion thread for a similar issue with digital signature.