Hello there,
if you have SIM questions you should ask your questions here :http://h30499.www3.hp.com/t5/ITRC-HP-Systems-Insight-Manager/bd-p/itrc-455
But your question, is SNMP configured on the server you want to monitor? Read community and source Ip should be set and also destination trap Community and ip or name of the SIM server. Then the SIM server needs at least the read community and if possible write community. Be aware that if you set a write community that the SNMP is V1 and can be sniffed and can then be used to change the config of your server if it spoofs the IP of your SIM server. Wbem is a saver option to monitor your server as that protocol is at least secure. Why do you want to use SNMP?