When choosing "Insert from file", Why doesnt the digital signature transfer with the rest of the file? How can I get the signature to transfer successfully with the rest of the file? (I've already changed the properties to accept and trust the digital certificate & signature but it still wont transfer when combining files or when inserting one file into another.)
A digital signature covers the content of a complete file. Acrobat does not have the capability to sign parts of a file. When you insert a signed PDF into another PDF file, the signature now does not cover the complete file, hence, it cannot be transfered to the new file. This is how digital signatures work.