Exchange 2003 Enterprise Event ID 9646

[kbrussel]

Been seeing every so often in my Application Event log:

Event Type: Error
Event Source: MSExchangeIS
Event Category: General
Event ID: 9646
Date: 7/16/2007
Time: 10:09:56 AM
User: N/A
Computer: EXCH03
Description:
Mapi session "/O=OURORG/OU=T/cn=Recipients/cn=username" exceeded the maximum of 32 objects of type "session".

This keeps the user from synchronizing their mailboxes using Outlook 2003 in cached mode. The only way I've found to get them around the error was to dismount and re-mount the stores--not the greatest of ways to resolve. I'm not crazy about increasing a default number of sessions, as referenced in MS's

http://support.microsoft.com/kb/842022

article. I'm already running Exchange 2003 Enterprise w/ SP2. Didn't seem to pose a problem while running SP1.

Any other ideas on this one?

 

[xmsre]

Is it a specific user or all users? If it's a specific user, examine the client computer carefully and follow the recommendations of 842022. As a last resort you could raise the limit.

If it's all users, take a look at your network. What's the MTU size set at? VPN clients? What version of Windows and SP1? Have you applied 898060?

 

[kbrussel]

I've seen it happen on a few users, myself included. Seems to happen only when the user is off-site, and coming in over either the corporate WAN (linking each site) or the VPN (when not at a company facility). So far, it's been on 4 users, each in different mailbox stores. All the clients are Outlook 2003 SP2 running on Windows XP SP2.

The Exchange Server's running Windows 2003 Service pack 2--so that supersedes 898060 (I'd think it includes the functionality of that update, though). You'd think the VPN client shouldn't have anything to do with it--being that it's just a straight Windows VPN (using DUNS VPN connector).

You'd think I'd see this with Blackberry users--they're usually the ones to be travelling and be on the VPN or at another site, but I haven't heard complaints from them.

 

[xmsre]

Closely examine the MTU size on the VPN client. THis has been an issue several times before, in fact, the mess created by the original MS05 019 fix which 898060 corrected was due to reducing the MTU size to a small value.

 

[kbrussel]

Here's the weird question that the article MS05-019 doesn't answer: It says the hotfix can be used on Windows 2003 SP1--but what if you have SP2 on the server? Was the "issue" corrected when SP2 came out, or just carried through?

 

[xmsre]

MS05 019 was corrected prior to SP2 so I assume so.