Try RMail PRE-Crime Services – When opening a PDF file containing a digital signature that was created from a self-signed certificate on RMail, the digital signature may display a Validity Unknown, Signature not verified, or At least one signature has problems message. This occurs when the digital certificate and digital signature associated with the PDF file have not yet been verified on the user’s system.
Please follow these steps to verify the digital certificates and digital signatures received from trusted sources (steps may vary by PDF reader program).
1. Open the PDF file in a PDF reader program.
2. Click on the Signatures button in the left-pane.
3. Right-click on the signature, and then click on Validate Signature.
4. Click on Signature Properties.
5. Click on Show Signer's certificate.
6. Go to the Trust tab and click on Add to trusted certificates.
7. Press Ok on the popup window.
8. Click on Ok in the Import Contact Setting popup window.
9. Wait a few seconds. The signature should now be validated.