Konica Minolta IEEE 802.1X Error 31
The EAP server certificate is in a format the printer cannot process correctly.
Error meaning
The EAP server certificate has an incorrect format.
This meaning is tied to the reviewed family/platform and subsystem below; do not reuse the number or wording by itself on a different printer family or protocol.
Applies to
bizhub C287/C227
- bizhub C287
- bizhub C227
Common formatting
These are formatting/lookup aliases for this reviewed condition, not separate error pages.
- 31
- ieee8021x-31
What usually causes it
- The server certificate or chain uses an unsupported or malformed encoding.
- A certificate deployment introduced an unusual format, incomplete chain, or corrupted certificate object.
- The authentication service presents different certificate data on different nodes.
What to try
Confirm the failure began around a certificate change
If code 31 appeared after a RADIUS certificate renewal or server migration, keep that change in scope.
Inspect the certificate format and chain on the server
Have the administrator verify the deployed certificate is valid, complete, and in a format supported by the C287/C227 802.1X implementation.
Compare multiple RADIUS nodes
In a cluster, make sure each node presents the same properly encoded certificate and chain.
Retry after correcting the certificate deployment
Do not repeatedly import random certificates into the printer. Fix the server presentation or use the manufacturer-supported certificate format.
After each corrective action
Retry the same operation that produced 31. If it now works, stop there rather than changing unrelated printer, network, supply, or service settings.
If the code returns
If code 31 remains with a known-good, supported server certificate, record the certificate format and firmware level for Konica Minolta support.
When service may be needed
This is a secure-authentication interoperability issue. Internal printer repair is not the first step; escalate with certificate and firmware details if the server deployment is valid.
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 product-family user guide. Candidate meanings are paraphrased from protocol-specific code tables; manufacturer prose must not be copied into public pages.