This article is designed to assist administrators with Layer accounts experiencing throttling errors when connecting to Office 365 mailboxes for mail send, triage, sweep, archive and calendar sync.
A typical error for this scenario can be rather generic, as follows:
The server cannot service this request right now. Try again later.
Log on to Office 365 as administrator, and click on the Help button.
Search for Increase EWS Throttling Policy
You should be presented with a "Run Tests" option, which should then provide some insights as to whether your account is throttled.
Wait some time, and you should see the results:
Next, you'll have the option to temporarily disable throttling, to provide some time to establish a permanent re-configuration.
Fill the form in as follows, and click "Update Settings"
Please note that this fix is temporary, and you should liaise with your IT team for a permanent fix.