I do not think you can changes this behavior. You can save on top of the old file. It is no longer possilbe to unsign pdf files. The only way to preserve an unisgned copy is to make Reader's behavior to Save As when a document is signed. While I understand why you might desire the Reader to behave this way, Adobe's choice is the safer choice for most users.
Thank you. So its not possible to just overwrite.
My initial question was about Acrobat Pro.
You mean Acrobat Pro not Reader ?
Yes, you can save over the existing file. You will get the overwrite confirmation dialog, but you do not have to create a new file if you don't want to. Of course if you want to do a Save As and create a new file you can, but you don't have to.
Acrobat (and Reader as well) has to perform the signing operation on the disk. We could sign in memory (and you wouldn't get the prompt to save the file), but we don't for security reasons. It's easier for the bad guys to modify the bits in memory just as you are about to sign (this stuff happens figuratively at the speed of light so it's not something you'd see) and to prevent legal documents from being compromised at signing time we write all of the file to disk (where it's harder for the bad guys to get to). If there were no hackers we could make the signing process a bit easier, but alas...
I hope this helps,
ltns . May I add, that it depends on the Signature Handler. Adobe's standard signature handler PPKLite, installed as PPKLite.api in the plug_ins folder of Acrobat and Adobe Reader, is requesting always a manual target file, but allows to overwrite the original.
Other signature handlers, e.g. like SigPDF, automatically are overwriting the original PDF file ... to prevent enterprise members to store the signed file outside the expected location (e.g. a network drive).
Is there anyway to automatically save the file without having the save as window to pop up?