If a Win2k8 R2 server should experience an alert from SCOM that the SMS Agent Host (e.g. the client) service is running, then the resolution is to simply restart the server. It is possible to prevent this on new server builds – Microsoft claims that restarting the server after installation of the SCCM client will keep the issue from occurring.
This alert is generated because the client crashes and then does a self-reinstall to recover from the error. You can confirm the client is crashing by checking for application event ID 1000 and 1001 for ccmexec.exe or system log event 7031. Microsoft has confirmed this is a recently discovered issue with SCCM 2007 clients on R2 servers and that the information is currently only published internally. The root cause is that Microsoft has found a problem in the code, but it is only fixed in SCCM 2011 and won’t be for SCCM 2007.
***Update 8/17/11***
John Nelson may have isolated the cause of the client crash, attributing it to execution of the Resource Monitor. Check out his post at http://myitforum.com/cs2/blogs/jnelson/archive/2011/08/17/158887.aspx
***Update 7/24/12***
Now there is a hotfix available! See http://support.microsoft.com/kb/2724939/en-us
t3chn1ck 
We have one server that keeps crashing the agent and reinstalling about every hour till you reboot, is that the issue you are talking about? We have uninstalled then reinstalled the client and rebooted – should that have fixed it now?
Jay, that sounds exactly like the problem we were having! Uninstall/reinstall and restart should fix it…which has worked twice for us. MS told me that if it doesn’t then to reopen the case. I would advise you open a case if it is not fixed. Please do follow up as I’d like to know if it does or does not resolve your situation!
Hi Nick, just following up. It’s happened on 3 servers now, 2 in a Physical DFS cluster and one VM. Uninstall/reinstall and restart fixed all 3.
That’s great – thanks Jay!
Hi – It is very interesting one. And do we have nay official communication from MS on this? Or would you be able to share the PSS incident number with me as I am facing MP issue for most of our secondary servers (as MP and SCCM client are sharing same component). So the case is even serious for me and we are working with MS on this since very long time.
Anoop, there is not an official document (e.g. KB article) published. Again, this is only known internally by MS/PSS. If you are experiencing the client crashing issue, then I would mention it to the engineer on your existing case.
Thank you. So there is no workaround for this issue as well.
According to PSS, the workaround is to restart the server with the client that is crashing
or
to restart the server after the client is installed initially. But nothing like a hotfix to install or a regkey to edit….
Ok, kool…that is what we are doing since last 4 months :-D
please refer the technet link as well
http://social.technet.microsoft.com/Forums/en/configmgrgeneral/thread/0e6e60e2-9b35-4a91-9035-4c20838a568e
Sorry for posting to such an old thread. But i have new information on this problem. I’ve opened an MS case for that problem and the first try was to reboot after initial client installation. But that was not a permanent fix. Therefore we’ve investigated some more time and found the root cause.
I think everyone knows that this is a bug in the ccm_caltrack.dll. But there are some other components causing this bug to occur.
Check your ETS (Event Trace Sessions). If there is a wdc. session started then stop and delete this session. This ETS is created by Resource Monitor and is needed by the application. Therefore if you stop the ETS, Resource Mintor will freeze its values.
BTW: Not only W2K8R2 will have this problem. Windows 7 as well…
I’ve posted a blog article about all the informations i have had.
The only “bad” thing is, that it is in german…
http://www.markus-tech-blog.de/2011/11/29/configmgr2007-agent-sturzt-stundlich-ab/
That’s awesome, thanks for posting the additional info! You’re right, the supposed fix from PSS has truly not been the real fix. Here is a decent translation of your posting into English – http://www.microsofttranslator.com/bv.aspx?ref=Internal&from=de&to=en&a=http://www.markus-tech-blog.de/2011/11/29/configmgr2007-agent-sturzt-stundlich-ab/
Thank you for this great info, i had been pulling my hair out on this one.
The only thing I have to add is that I am seeing a status message of 669 (2 in fact) each time this happens. So in order to determine which machines this is happening on, run the report Status Messages -> All messages for a specific message ID and query for message ID 669.
http://cornasdf.blogspot.com/2012/01/ccmexec-crashing-on-windows-2008-r2.html
Woohooo!! Now there is a hotfix available! See http://support.microsoft.com/kb/2724939/en-us
Excellent! Thank you Markus!!!!!!