Error on New Server - Informant not Installed

Hi All, im new to Nagios ( have taken over a role where its already been installed and configured ), however am having an issue with a new server and its monitoring. I have installed SNMP_Informant and configured the SNMP service the same as all the other monitored servers, however I cant get this one to play the game. Its a Server 2000 box. I can get to it using Getif, and get readings from it, but just not from Nagios. Does anyone have any clues as to where I can look ?

Cheers

Paull

Plugin Output:
No Output, INFORMANT is probably not installed, or incorrect SNMP Community

servicedesc: informant_disk_h
servicestate: UNKNOWN