We have found a way of removing machines from reports that are no longer in AD (ie the machine object has been deleted) or the computer account has been disabled. ie where v_AgentDiscoveries.AgentName = 'SMS_AD_SYSTEM_GROUP_DISCOVERY_AGENT' and date is < yesterdays date. I would like to do the same for a few collections but I can't seem to find the 'SMS_AD_SYSTEM_GROUP_DISCOVERY_AGENT' field available in any of the queries. We can't use AgentTime because it's not reliable enough for us. Does anyone know where to find this?

look at this thread discussin on same topic http://social.technet.microsoft.com/Forums/en-US/configmgradminconsole/thread/d1513223-d76d-41bc-b4a3-8d2d6427b1ee/#ac8a1cb2-3f69-417a-a202-0404f1ca7c6a you may can create collection as given in above thread and use special delete to remove them at one go.Eswar Koneti | My Tech blog: ESKONR.COM

Hi Eswar, Thanks for the link. We would like to exclude 'old' machines without actually deleting them from SCCM. We need the inventory information etc to remain for compliance. Our problem with using machines that have not reported a hardware inventory for x days is that it doesn't reflect AD. ie some machines are in AD but the have been offline for x days so they aren't in the collection. Using v_AgentDiscoveries.AgentName for the reports is perfect because it means that the reports show all AD machines (give or take 24 hours) so a disabled machine disappears pretty quickly. If only we could use this field for collections.

then create a collection based on agentdiscovery to list computers that are not reported to site server.for this you can use subselected quiries given here on this http://eskonr.com/2011/12/sccm-collection-sub-selected-quiries/ if you remove the computers that are not reported to site sevrer for x days,they will be removed from database but they wiill be rediscovered based on heartbeat so only think about inventory info.Eswar Koneti | My Tech blog: ESKONR.COM

then create a collection based on agentdiscovery to list computers that are not reported to site server.for this you can use subselected quiries given here on this http://eskonr.com/2011/12/sccm-collection-sub-selected-quiries/ if you remove the computers that are not reported to site sevrer for x days,they will be removed from database but they wiill be rediscovered based on heartbeat so only think about inventory info.Eswar Koneti | My Tech blog: ESKONR.COM