Exchange server can't receive from AOL; MapiExceptionNamedPropsQuotaExceeded

We have Microsoft Standard Exchange 2007. Sometime recently we have suddenly lost the ability to receive emails from AOL. As far as I can tell, we are receiving all other email normally.

The only anti-spam solution we use is a blocklist from zen.spamhaus.org. I've temporarily disabled it with no change. I didn't think it would make a difference anyway since the aol servers don't appear to be in zen.

We use OpenDNS as our DNS provider, but it's not blocking aol.com.

We are able to SEND to aol.com and these messages are received so it's not like they are blocking our domain.

============================================
UPDATE 1: Here's a typical aol log (I chopped out the IP's and other stuff):

,<,EHLO imr-da02.mx.aol.com,
,>,250-mail.mydomain.com Hello [205.188.105.144],
,>,250-SIZE,
250-PIPELINING,
250-DSN,
250-ENHANCEDSTATUSCODES,
250-STARTTLS,
250-AUTH GSSAPI NTLM,
250-X-EXPS GSSAPI NTLM,
250-8BITMIME,
250-BINARYMIME,
250-CHUNKING,

,250 XEXCH50,
<,MAIL From: SIZE=8356995,
,08CBB8907FCC1A80;2009-08-18T18:37:33.812Z;1,receiving message
,250 2.1.0 Sender OK,
<,RCPT To:,
,250 2.1.5 Recipient OK,
<,DATA,
,354 Start mail input; end with .,
,+,,
,,SMTPSubmit SMTPAcceptAnySender SMTPAcceptAuthoritativeDomainSender AcceptRoutingHeaders,Set Session Permissions
,>,"220 mail.mydomain.com Microsoft ESMTP MAIL Service ready at Tue, 18 Aug 2009 14:37:45 -0400",

======================================================================
UPDATE 2:

Using the Microsoft Troubleshooting assistant, the mail tracking results for a specific email gave this error message:

550 5.2.0 STOREDRV.Deliver: The Microsoft Exchange Information Store service reported an error. The following information should help identify the cause of this error: "MapiExceptionNamedPropsQuotaExceeded:16.18969:23010000, 17.27161:00000000E4000000000000000000000000000000, 255.23226:00000000, 255.27962:7A000000, 255.27962:56000000, 255.17082:00090480, 0.16993:80030400, 4.21921:00090480, 255.27962:FA000000, 255.1494:00000000, 255.26426:56000000, 4.6363:0F010480, 2.31229:00000000, 4.6363:0F010480, 2.22787:00000000, 2.22787:00000000, 2.22957:00000000, 2.19693:00000000, 2.17917:00000000, 2.27341:00000000, 2.22787:00000000, 4.5415:00090480, 4.7867:00090480, 4.4475:00090480, 4.4603:00090480, 4.5323:00090480, 5.10786:000000004E414C2D4D41494C303100100F010480, 255.1750:00090480, 0.26849:00090480, 255.21817:00090480, 0.24529:00090480, 4.18385:00090480".

Answer

From your new information, you can read about named properties here:

http://msexchangeteam.com/archive/2009/04/06/451003.aspx

There is apparently a bug/limitation that is fixed in UR8 (supposedly) with information here on workarounds:

http://technet.microsoft.com/en-us/library/bb851493.aspx

You apparently need to configure a number upwards of the maximum since the default is in the 16k range. More information about this value can be found here:

http://technet.microsoft.com/en-us/library/bb851492.aspx

and you might be seeing these errors in your event log

http://technet.microsoft.com/en-us/library/bb851495.aspx

If you're not on UR8 or UR9 for Exchange, I would first start by updating the system and see if the error persists. Otherwise, start looking at the workarounds.

It also looks like this HeaderFilterAgent

http://www.codeplex.com/HeaderFilterAgent

can be used to strip the unwanted X-headers from filling up your quota