Error when sending emails with Outlook.com - The revocation function was unable to check revocation because the revocation server was offline

In certain cases when trying to send email with Outlook.com in Print2Email, the following error message can occur: The revocation function was unable to check revocation because the revocation server was offline.

The error is related to an SSL/TLS certificate validation issue, specifically that the system is unable to verify the certificate revocation status. This issue is not related to the Print2Email configuration itself, but rather to the system being unable to validate the SSL certificate during the secure connection to Microsoft 365. This is typically environment-specific.

Most common issues:

• The machine cannot reach the certificate revocation servers (CRL/OCSP) due to:
  • Firewall or proxy restrictions
  • Network filtering or security policies
• Missing or outdated root/intermediate certificates
• Strict security settings on the affected workstation/server

Recommended actions to resolve the problem:

• Check firewall/proxy settings, or temporarily disable firewall/proxy settings.

  Make sure SSL inspection or filtering is not blocking certificate validation.

• Update Windows certificates

  Run Windows Update to ensure the latest root and intermediate certificates are installed.

• Temporarily disable SSL inspection

  Some endpoint security solutions interfere with certificate validation.