Konica Minolta SMTP 3012 Error
SMTP 3012 means a certificate required for the secure e-mail operation is missing on the bizhub C368/C308/C258.
Error meaning
A destination certificate required for the secure mail operation is missing.
This meaning is tied to the reviewed family/platform and subsystem below; do not reuse the number by itself on a different printer family or protocol.
Applies to
Konica Minolta bizhub C368/C308/C258 network services
- bizhub C368
- bizhub C308
- bizhub C258
Common formatting
These are formatting/lookup aliases for this reviewed condition, not separate error pages.
- SMTP 3012
- 3012
- SMTP3012
What usually causes it
- A required destination or trust certificate is not installed.
- The secure mail configuration changed and now expects a certificate the device does not have.
- A certificate may have expired or been replaced on the mail side, leaving the printer's trust configuration incomplete.
What to try
Confirm the failed function uses secure mail
Check whether TLS, S/MIME, or another certificate-dependent mail feature is actually configured.
Check the printer's certificate/trust settings
Use the device's supported administrator interface and compare installed certificates with the organization's mail requirements.
Check the mail-side certificate change
If the mail service recently changed certificates, ask the administrator whether the printer needs an updated trusted certificate.
Retry after the certificate configuration is corrected
Send the original mail operation again and verify the code clears without disabling certificate validation.
After each corrective action
Retry the same operation that produced SMTP 3012. If it now works, stop there rather than changing unrelated printer, network, or service settings.
If the code returns
A recurring 3012 after the expected certificate is installed can indicate a trust-chain, certificate-selection, or policy mismatch.
When service may be needed
Certificate changes affect security. If you are not the mail/device administrator, stop at verification and have the responsible administrator make the certificate change. Do not disable trust checks as a shortcut.
Continue with guided troubleshooting
If the printer still is not working after the reviewed checks, carry this verified error context into the guided troubleshooter.
Related information
Verified source
Official Konica Minolta bizhub C368/C308/C258 Error Code List; protocol context is part of the identity.