Exchange Web Services (EWS) throttling in Exchange Online
Throttling in Exchange Web Services (EWS) significantly impacts Office 365 migration processes by regulating the flow of data between Office 365 servers. Microsoft imposes throttling limits to prevent excessive resource consumption, ensuring server stability and performance. These limits can slow down migration speeds, cause connection disruptions, or lead to errors if not managed properly.
How to Prevent EWS throttling in Office 365?
Preventing EWS (Exchange Web Services throttling) isn't straightforward because Microsoft controls this process. However, there are precautions you can take to minimize its occurrence.
- Maintain intervals between multiple data migrations
- Avoid running heavy concurrent tasks during migration.
- Limit frequent requests to the same mailbox during Office 365 operations.
- Minimize activities within the mailbox as much as possible.
Steps to increase EWS throttling policy limits in Microsoft 365
Changing throttling policies in Exchange Online by yourself isn't possible anymore. Previously, this could be done using remote PowerShell, but Microsoft removed those options. However, you can temporarily increase EWS throttling limits in Microsoft 365 admin center or contacting Microsoft support.
- Login to Microsoft 365 Admin Center
- Click ‘...Show all’ in the left pane
- Navigate to ‘Support’ > ‘Help & support’
- Type ‘Increase EWS Throttling Policy’ in the search bar, and press Enter key then click the ‘Run Tests’ button
- Wait till the diagnostics test completes. Next, choose either 30, 60, or 90 days to disable the EWS Throttling Policy. Ensure to check the acknowledgement checkbox and then click the ‘Update’ button
- Exchange Web Services (EWS) throttling policy updates has been started. It will complete within 15 minutes.
- After 15 minutes, perform the test (Step 4) to confirm that the throttling has been disabled.
