Zenoss can use information from SNMP-informant to get SNMP information from windows devices. First, you must install the free version of snmp-informant from: http://www.snmp-informant.com
To make sure SNMP Informant is running and setup correctly, run this command to walk the SNMP Informant MIB:
snmpwalk -v1 -c<community> <server> 1.3.6.1.4.1.9600
This command will return some performance information if SNMP-informant is configured and running correctly.
Once this is configured properly SNMP information is gathered and used by the Zenoss system the same as any other device sending SNMP traps.