Linux software list, Map,issues

when i scan linux machines, there is nothing listed down in the installed software page, can you help me if i am missing something while scanning, linux box snmp is enabled , flavours are : redhat, debian, sco, sun

please help as i have posted this many times,

i do face loads of issues with Opmanager, like my system hanging and yahoo messenger pops up ,bla bla bla

but firstly i want to sort this out

i tried as you said, snmp is configured but doesnt fetch details

Loading MIBs .\mibs\RFC1213-MIB
Done.

Loading MIBs C:\AdventNet\ME\OpManager\mibs\HOST-RESOURCES-MIB
Done

Sent get request to 172.16.2.91 : 161
Request Failed: Get Response PDU received from 172.16.2.91
Error Indication in response: There is no such variable name in this mib.
Errindex: 1

Sent get request to 172.16.2.91 : 161
Request Failed: Get Response PDU received from 172.16.2.91
Error Indication in response: There is no such variable name in this mib.
Errindex: 1

Sent get request to 172.16.2.91 : 161
sysDescr.0:Linux debian-vm 2.4.27-2-386 #1 Mon May 16 16:47:51 JST 2005 i686

Sent get request to 172.16.2.91 : 161
Request Failed: Error: Request Timed Out to 172.16.2.91