Skip to main content


Exchange 2010 Mailbox Moves Require NetBIOS Name Resolution

During a recent Exchange 2010 Deployment, my customer was experiencing 3 different Exchange 2010 issues that were all solved with the same fix.
Issue #1:
Customer was unable to move mailboxes from one database to another on the same Mailbox Server or between Mailbox Servers. The following error was returned when attempting to move mailboxes:
MapiExceptionNetworkError: Unable to make connection to the server. (hr=0x800004005, ec=2423)
A screen shot of the error follows:

Issue #2
Customer was seeing the following error in their Application Event Log on each Exchange 2010 CAS Server:
The Microsoft Exchange Mailbox Replication service was unable to process jobs in a mailbox database. Error: MapiExceptionNetworkError: Unable to make connection to the server. (hr=0x80004005, ec=2423)
A screenshot of the error follows:

Issue #3
Unity Connection was not able to place voicemail messages into an Exchange 2010 mailbox. Unity Connection uses EWS (Exchange Web Services) to perform this function, and Unity Connection was not able to perform the required EWS Subscribe Request in order for this functionality to work correctly. To troubleshoot this issue, a tool called EWSEditor was downloaded from Microsoft, which can be found here: After using the EWSEditor Tool to connect to the Exchange 2010 CAS Servers, the following error was returned:
The mailbox database is temporarily unavailable. Microsoft.Exchange.WebServices.Data.ExchangeService.InternalSubscribeToPullNotification
A screen shot of the error follows:

After a good deal of research and testing, I discovered that CAS Servers must be able to resolve the server names of Mailbox Servers via NetBIOS name resolution, otherwise mailbox moves fail. In my customer’s case, the CAS Servers were not able to resolve NetBIOS names of the Mailbox Servers. For example, pinging MB01 from a CAS Server failed, but pinging the FQDN of worked successfully. To resolve this issue, I added as a DNS Search Suffix on the CAS Servers. See the screenshot below:

Once the proper DNS Search Suffix was added to all CAS Servers I was able to ping all Mailbox Servers via NetBIOS name. This simple fix not only resolved all mailbox move issues, but also resolved the EWS Subscribe problem that Unity Connection was experiencing.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Follow Us