When Office365 throttles a user, it slows down the GDPR scanner - This is how to avoid that.
What is throttling?
Throttling is a security mechanism that keeps a server healthy and responsive. It is called "throttling" because it limits the workload coming through the server by regulating network traffic and minimizing bandwidth congestion. As a result, you may experience slow Internet and performance speeds, which in turn can impact the speed of your backup or restore.
Throttling is a general condition that all Microsoft Office 365 applications have to deal with and it is not something that can be affected or changed through configuration or regular troubleshooting.
Microsoft offers only a limited amount of bandwidth to each of their Office 365 or OneDrive customers and applications installed by those customers cannot go beyond those limits. Allocation of bandwidth is based on the number of licensed users on the platform.
Disable EWS throttling in Exchange Online
1. Log in to the Office 365 admin page with your Global admin credentials.
2. Open the Admin app.
3. In the left navigation pane, select Support and then New service requests.
4. In the search field, search for throttling. Select Increase EWS Throttling Policy from the list and press Enter.
5. Select Run Tests. Diagnostic tests will run.
6. Select the duration in days. The options are 30 days, 60 days, and 90 days. Check the checkbox to acknowledge the change and then select Update Settings. -> choose 90 days.
7. You will see a message showing that the update to Exchange Web Services (EWS) throttling policy has been successfully initiated. The update will complete within 15 minutes.
8. After 15 minutes run the test again to check if the changes are applied. This time you will see that Exchange Web Services (EWS) is currently not throttled.