If you are trying to migrate a Mailbox from on premise to Office 365 and see the following error:
The DataImportTimeout property may be set too low as by default it is set to 60 seconds and can be set up to 30 minutes. You may find that the migration may have started as depending on where the commuication failed the move request may have been processed.
To resolve this:
To isolate the issue, you may check how it works if you increase the timeout with the following steps:
- On the Client Access server, open the following file with a text editor such as Notepad:
- Locate the following section in the web.config file:
<!– Mailbox Replication Proxy Server configuration –>
- Make sure value of the IsEnabled property is set to true.
- Check the value of the DataImportTimeout property. The minimum value is one minute (00:01:00), and the maximum value is 30 minutes (00:30:00).
- Set a higher value, but make sure the value is less than 30 minutes.
- The recommended value for this field should be 00:20:00 (20 minutes).
- After the values are configured correctly, save and close the web.config file.
- Restart IIS