| Previous | Next |
| STATUS_SMB_BAD_CLUSTER_DIALECT | STATUS_SPACES_FAULT_DOMAIN_TYPE_INVALID |
STATUS_SMB_GUEST_LOGON_BLOCKED
STATUS_SMB_GUEST_LOGON_BLOCKED is an intentional client-security decision. The remote share attempted unauthenticated guest access, but Windows policy blocked it. It is not evidence that the server is unreachable or that a normal named user account failed authentication.
How to narrow it down
Microsoft documents that guest logons do not support standard SMB signing and encryption protections. The preferred remedy is to configure the server or appliance to use authenticated access with a named identity and a current SMB dialect. Enabling insecure guest logons should be a narrowly reviewed exception, not a default repair step.
When examining this result, collect the server's advertised authentication behavior, client SMB policy and the relevant SMBClient/Security event. That identifies whether the server genuinely requires guest access or whether a configured account fell back to guest unexpectedly.
Evidence that matters
- Confirm whether the server supports named authenticated SMB access.
- Inspect SMBClient/Security events for rejected guest authentication.
- Prefer authenticated SMB with signing/encryption over enabling guest access globally.
References
- Microsoft Open Specifications: NTSTATUS reference
- Microsoft: insecure guest logons in SMB2 and SMB3
- Microsoft: SMB security enhancements
Looking for a different code? Search another status or error code.