Running List of Unresolved Problems ...

NDRs Sending to MS Mail POs

I'm running an Exchange (4.0sp2) MS Mail MTA instance to deliver mail
between MS Mail POs as well as to/from Exchange.  Periodically I see non
delivery reports going to MS Mail users.

There appear to be two relevant events in the log:

Event 1; Event ID: 4532; Type: Error

description:

The CreateFile call failed after 61 attempts over 60 seconds.  
The call was made on file \\server\poshare\KEY\000000C2.KEY with open
access mode 0xC0000000 and share mode 0x00000001. 
The system error return code was 32.

Event 2; Event ID: 4304; Type: Error; Category: NDR

description:

[008] Unable to deliver mail due to mailbag contention. Message was not
delivered to ...

I cannot believe that mailbag contention should result in an NDR!  Has
anyone seen this behaviour?  Or, more importantly, is there a way to stop
it?

NDRs Sending MS Mail to Remote Exchange Users via x.400 Connector

I'm sending MS Mail through an Exchange Site to another (remote) Exchange
Site via an x.400 connector.  Most MS Mail gets through, but some messages
generate NDRs like this:

----------------------------
Your Message

    To:  Mail Ping
    Subject: Afternoon delight ...
    Date:  1996-10-08 15:34

Was not delivered for the following reasons:

    Delivery failed to X400:C=CA;A= ;P=Org;O=DestSite;S=Ping;G=Mail;.
    Reason: 0 (transfer failed)
    diagnostic:  2 (MTS congested (Exchange MTA has a routing problem))
    MSEXCH:MSExchangeMTA:OriginSite:SERVER.

Original message body follows...
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