Veeam Explorer for Microsoft Exchange Timeouts

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A possible issue when restoring a large number of items with the Veeam Explorer for Microsoft Exchange can be operations timing out. Especially when using the advanced search feature in large mailboxes.

Error messages related to these timeouts can pop-up during the restore with the following message:

Connection to server was unexepectedly close. See log file for details.

Error: This request operation sent to net.tcp:// did not receive a reply within the configured timeout (00:01:00). The time allotted to this operation may have been a portion of a longer timeout. This may be because the service is still processing the operation or because the service was unable to send a reply message. Please consider increasing the operation timeout (by casting the channel/proxy to IContextChannel and setting the OperationTimeout property) and ensure that the service is able to connect to the client.

In the Veeam Explorer for Exchange log files (C:\ProgramData\Veeam\Backup\ExchangeExplorer\Logs) these errors may also be present:

Error: The message could not be transferred within the allotted timeout of 00:01:00. There was no space available in the reliable channel’s transfer window. The time allotted to this operation may have been a portion of a longer timeout.

Error: Unable to read data from the transport connection: A blocking operation was interrupted by a call to WSACancelBlockingCall.

Error: A blocking operation was interrupted by a call to WSACancelBlockingCall

To resolve this issue, the timeout can be increased by editing the Exchange Explorer config.xml file. To do this, follow these steps:

Make sure that the Exchange explorer is closed and no restore sessions are running.

If you are performing the restore from a Veeam for Microsoft 365 server, make sure no jobs are running and stop the Veeam Services:

  • Veeam.Archiver.Proxy
  • Veeam.Archiver.Service

Next, open a text editor and edit the file: C:\ProgramData\Veeam\Backup\ExchangeExplorer\Config.xml

Add the following text between the tags in the file: <WCF OperationTimeout=”3600″ />. Don’t modify any other lines in this file.


<WCF OperationTimeout="3600" /> 

Finally, save the file and start the Veeam for Microsoft 365 services again.

After following these steps try the restore again. The time-out issues should now be resolved.

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