Can we configure a certificate to adobe reader for signing purpose programatically ? (perhaps using Windows batch file, shell-script or official library available from adobe)
The certificate needs to be configured (within Adobe Reader) with the "use of signing" usage option.
The Acrobat SDK describes all programming interfaces in Acrobat, and a few in Reader too. Neither one has an interface for this, so far as I know.
What about just adding it to the Windows Certificate Store, where Reader can find it?
The reader is able to find it i.e. the certificate is already installed in cert-store (windows) or keychain (macOS). In order to configure the reder, below are the manual steps that we follow:
1. Go to Edit > Preferences in adobe reader
2. Choose the "Signatures" category
3. Choose "More" button in "Identies & Trusted Certificates" section
4. Choose "Use for Signing" option for one of the required certificate among all the available/installed certificates in "Digital IDs" section
The ask here is if we can write an script/program/application that can configure the reader (do the above steps) automatically to use that particular certificate for signing purpose.
There is a tool for admins for doing this – see https://www.adobe.com/devnet-docs/acrobatetk/