MC1227454 EWS begins being disabled October 1, 2026 · fully retired, including allow lists, April 1, 2027

EWS App ID Decoder

The EWS usage report identifies applications still calling EWS by Application ID only — it does not resolve them to names. Paste the exported CSV (or any list of Application IDs) to get application names, vendors, and the recommended action for each, with sources.

Everything runs in your browser. Nothing is uploaded, logged, or stored.

Microsoft 365 admin center → Reports → Usage → Exchange → EWS usage → Export. Bare Application IDs (e.g. copied from Entra sign-in logs) work too.

File never leaves the browser.