SNMP Query fails with Error: Error in packet. Reason: (genError) A general failure occured

hi Utnapischtim​  The fact that the same failure occurs on both Windows Server 2022 and Windows 11 is interesting. It makes a problem with the individual machines less likely and points more toward the Windows SNMP implementation or the particular OID being queried.

The important clue is that the walk succeeds for:

.1.3.6.1.4.1.77.1.1.1.0

.1.3.6.1.4.1.77.1.1.2.0

.1.3.6.1.4.1.77.1.1.3.0

and then returns genError specifically on comType.0.

A few things would be worth checking:

Query that OID directly rather than using snmpwalk to confirm the behavior.

Try SNMP v2c as well as v1 and compare the result.

Check whether the same OID fails when queried using another SNMP client/tool.

Capture the SNMP traffic with Wire shark. The response packet should show whether Windows is returning genErr and, importantly, what error-status/index is being returned.

Check the SNMP service configuration and Windows event logs for anything related to the SNMP service.

It may also be worth testing a few OIDs before and after .1.3.6.1.4.1.77.1.1.3.0 rather than assuming the failure means the entire MIB walk is broken.

Since the failure is reproducible on two different Windows versions, the packet capture would probably be the most useful next step. It should help determine whether the problem is with the Windows SNMP agent returning genErr for that particular MIB object, or whether something is happening in the SNMP client during the walk.

If someone can reproduce it on a fully patched Windows 11/Server 2022 system, comparing the actual SNMP response packet would also be very useful.