EWS shuts down in October, but your deadline is 31 August
On 1 October Exchange Online starts disabling EWS, and on 1 April 2027 it disables it for good, with no re-enablement. But one detail turns the calendar on its head: from October, leaving EWSEnabled set to True with an empty allowed-application list starts to mean "block everything", and if you do not write that list before the end of August, in September Microsoft writes it for you based on whatever it saw running. What to look at in the usage report, the exact commands, why that automatic list fails both by omission and by excess, and the gaps Graph still does not cover according to Microsoft's own roadmap.
Microsoft 365
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