we're struggling with one "feature" of Adobe Acrobat Reader DC. After signig a document with a certificate, there's always a "Save as" prompt. We can never sign the original file but always have save it as a new one. Is there a way to fix it?
We've tried to disable the protected mode on startup but it didn't help, popup's still coming.
This not a bug or a mistake. When you sign a file you *must* save it, so it can be blocked from further edits.
That's one of the main features of a digital signature, and can't be turned off. However, you should be able to overwrite the original when doing so, although it's not recommended (just in case you want to go back to an unsigned version).