I get this error "Calendaring agent failed in message save notification with error 0x800703eb on user@contoso.com: /Calendar/test-2.EML" on an exchange 2007 server. I know this has been a problem on 2003 but 2007 also? Please tell me someone has seen or heard about this? It is a single user mailbox migrated from 2003 to 2007.

Did you create this as a new resource mailbox or migrate it over from 03 ?

Migrated from 2003 to 2007...it is actually a user mailbox not a resource (probably little difference though).

Quite a bit of difference. E2k7 doesn't use the calendaring agent, so you'll need to change the mailbox type to resource.

Change it to a resource mailbox even though it really isnt one? Maybe I wasnt specific enough... This user is trying to schedule a meeting with other people, but when users accept the request is when i start seeing the 8199 errors in the application log. The error ocurrs on the user mailbox, not the resource mailbox the user specifies as the location.

Ok, now I"m with you. Are all mailboxes in question on 2007 ?

Fortunately, there is only one mailbox in question (having the issue). But yes, all other mailboxes in our environment are 2007 as well.

Did you install the calendaring agent on the 07 server (it shouldn't install....)

Honestly, I dont know what the calendaring agent is. I am a Neo Exchange Admin...I came into it around Exchange 2003 SP2, but have lived and breathed it since (and born again with E2K7). We are still in CoExistance mode with our earlier 2003 servers...I just completed the 3000 user base migration, but the 2003 infrastructure is still online. You think they may be causing issues? We do still have a 2003Public Folders server running that is replicating to a 2007, but the errors Ive mentioned are on the 2007 servers. Im completely confused now, I had no idea the "Calendaring Agent" that is failing isnt even part of Exchange 2007. Sheesh...going for a run but be back soon in case you post anything new. Thanks for the help...

Sorry i was using bad terminology. I meant the exchange auto-accept agent http://www.microsoft.com/downloads/details.aspx?FamilyId=3D0884E6-C603-491D-BF57-ACF03E046BFE&displaylang=en

Hit post to quick. So i'm just curious if this agent is installed on the 03 server, which well could be causing the issue. I assume 03 is running on Sp2 ?

Correct, the 2003 nodesare running SP2...will check if the auto-accept agent is installed.

According to this article http://technet.microsoft.com/en-us/library/aa996223.aspx I would find the autoaccept agent in the COM+ area...I did not find it there nor did I find it in the filesystem on the 2003 cluster nodes.

Did you ever get a answer for this? We are having similar issues with a few of our user mailboxes migrated from 2003 to 2007 and we do not have the Auto Except Agent running on our 2003 cluster either. The only real insight we have seen is this post by a German guy: http://translate.google.com/translate?hl=en&sl=de&u=http://msg-blog.de/2007/09/28/exchange-2007-calendaring-agent-meldet-excdo-events-8199-8206-und-8213-bei-mehr-als-1300-serienterminen/

Greetings I believe this is now a known issue to Microsoft and as I understand it SP1 does not have the issue and a pre-SP1 patch is going to be released in the next couple of days. Cheers, Scott

Oh trust me, SP1 has the issue because we are running on SP1 now and are still experencing the same thing. Looks like update rollup 6 will take care of it for users without SP1. I hope update rollup 1 for SP1 will take care of the issue as well.

Looks like in fact rollup 1 for Exchange 2007 SP1 will take care of the problem. http://support.microsoft.com/?kbid=945684 943371 (http://support.microsoft.com/kb/943371/) Event IDs 8206, 8213, and 8199 are logged in an Exchange 2007 environment

Hmmm, well I am still getting EXCDO 8206 errors and am on Update rollup 3 for Exchange 2007 SP1 so do not think the issue has been resolved.