Hi Ed,
The syntax for adding domain user is:
useradmin domainuser add win_user_name -g {custom_group|Administrators|"Backup Operators"|Guests|"Power Users"|Users}[,...]
win_user_name is the Windows domain user whose name or Security ID (SID) you want to assign to a customized or predefined group.
Please refer to this help page on useradmin domainuser command.Using this I could add the user as:
> useradmin domainuser add DOMAIN\snmpv3user -g snmpv3group
SID = S-1-5-21-1939535855-3574135614-826000282-1143
Domain User <DOMAIN\snmpv3user> successfully added to snmpv3group.
Also please make sure that this user is added to the appropriate group i.e snmpv3group that has the required role i.e. "snmpv3role" with "login-snmp" access.
>useradmin role add snmpv3role -a login-snmp
> useradmin group add snmpv3group -r snmpv3role
Regards,
-Amir