Mailbox Move Error - MAPI or an unspecified service provider - Federated Infrastructure - Site Home

Although not an Exchange Ranger myself, I've worked with several of these folks and as long as I am within their sphere of influence, things seem to go well for me. Occasionally, however, I work alone and forget some of their rules. The most important rule, when relating to Exchange troubleshooting, is starting from the bottom of the OSI stack and working your way up.

I was working with a customer on a very simple mailbox move from Exchange 2000 to Exchange 2003, same subnet. The majority of my mailboxes were returning an error very similar to the following:

<item adsPath="LDAP://INSERT PATH HERE" class="user">
<progress code="27" milliseconds="803532">Moving messages. Inbox (14/37)</progress>
<summary isWarning="false" errorCode="0xc1050115">
An unexpected, unknown error has occurred. MAPI or an unspecified service provider. ID no: 80040115-0000-00000000
<details>
</item>

The event log contained the following events (some data removed to protect the guilty).

Event Type: Error
Event Source: MSExchangeAdmin
Event Category: Move Mailbox
Event ID: 1008
Date:  5/19/2005
Time:  10:54:48 PM
User:  N/A
Computer: DESTINATION
Description:
Unable to move mailbox 'Some Dude'.
Error: An unexpected, unknown error has occurred.
MAPI or an unspecified service provider.
ID no: 80040115-0000-00000000

Event Type: Error
Event Source: MSExchangeAdmin
Event Category: Move Mailbox
Event ID: 1023
Date:  5/19/2005
Time:  10:54:48 PM
User:  N/A
Computer: DESTINATION
Description:
Unable to set a property on the message store on 'SOURCE'. Result: Network problems are preventing connection to the Microsoft Exchange Server computer.
An unexpected, unknown error has occurred.
Microsoft Exchange Server Information Store
ID no: 80040115-0514-000006be

Event Type: Error
Event Source: MSExchangeAdmin
Event Category: Move Mailbox
Event ID: 9172
Date:  5/19/2005
Time:  10:54:46 PM
User:  N/A
Computer: DESTINATION
Description:
Failed to copy messages to the destination mailbox store.
Error: An unexpected, unknown error has occurred.
MAPI or an unspecified service provider.
ID no: 80040115-0000-00000000

Looking at the Knowledge base, I was told it could be any of the following:

Network Connectivity
DNS Lookup Failures
Anti-virus Software
Database Corruption (Requiring offline defrag and IS Integrity Check)

So I focused my efforts on #4. After all, I had already verified that DNS is working properly and disabled the AV software. Further, I had changed the settings on the NICs from Auto-Sense to 100Mbps/Full Duplex. And the organization in question had several other issues on the AD side indicating that things were not in the best order. At the completion of running several passes of ESEUTIL and ISINTEG, only about half the mailboxes were failing. After a few more hours of chugging along, I asked the customer, "are these machines actually on the same switch?" The answer was no. I pleaded to them to plug the two machines into the same switch and, volia, the remaining mailboxes not only finished 100% without errors, but they finished in as much time as it took to move the first 5 mailboxes.

Start from the bottom and work your way up.