One of the processes we need to complete when running migrations of archive data to Microsoft 365 mailboxes is to disable Exchange Web Services (EWS) throttling. This allows migrations to run at speed, without disabling throttling, migrations run at about 80% less throughput.
The process was to have our customers log a Microsoft Premier Support case and it would then be completed in the back-end by MS engineers. A few years ago, this would take about 2-3 days to complete, more recently it is usually completed within 24 hours.
Now, Microsoft have made the process simpler and faster by allowing admins to disable EWS throttling from the Microsoft 365 admin centre.
To complete, login to the Microsoft 365 admin centre and click on Help (?). In the Need Help? Section type in Increase EWS Throttling policy, the following screen should be presented.
Click on Run Tests and wait for it to complete.
The tests will come back to say EWS is throttled. At this stage you can choose either 30, 60 or 90 days for the duration. Choose your duration, click acknowlege and click Update Settings.
If it has been applied correctly the following screen will be presented. We have Success!
The process takes about 15-30 minutes to complete on the tenant, running the diagnostic tests again after this time should come back to say that EWS are not currently throttled.