These are user agent strings, which you might encounter when inspecting the IIS logs on your Exchange Server.
| User Agent | Used By |
|---|---|
| SkypeSpaces/… | The Teams backend (originally codenamed SkypeSpaces, hence the name) queries free/busy or OOF data from Exchange via AutodiscoverV2/EWS to populate the Teams Calendar and presence features |
| Microsoft.Skype.Presence.App/1.0 | The presence service of Teams / Skype for Business to determine calendar‑based presence (e.g., In a meeting, Out of office) by reading Exchange calendar/OOF via EWS. |
| AMProbe/OAUTH/Exchange | Managed Availability (Active Monitoring) probe to simulate client access to validate end‑to‑end health. OAuth indicates that it was used to authenticate. |
| SchedulingService | Used for delegate scheduling scenarios from Teams / Skype for Business via EWS. |
| MicrosoftNinja/1.0 Teams/1.0 | Teams Calendar access (EWS). |
| ASProxy/CrossForest/EmailDomain/EXCH/<version> | Availability Service proxy used in cross‑forest free/busy scenarios. Includes hybrid scenario requests. |
| Outlook/<version> | Outlook’s MAPI/HTTP traffic. |
| OWA/<version> | OWA EWS calls. |
| ExchangeServicesClient/<version> | EWS Managed API |
| Outlook-iOS/<version> Outlook-Android/<version> | Outlook mobile REST / EWS calls. |
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