How can I verify mailbox accessibility using EWS​?​

Answer:

You can verify independently whether a mailbox is accessible using EWS by performing these steps:

1. Browse to https://testconnectivity.microsoft.com. This is a Microsoft-owned tool.
2. If using Office 365, click on the Office 365 tab.
3. Select Service Account Access (Developers) and click on Next.
4. Specify the target mailbox email address.
5. Specify the service account user name (if using admin credentials on the connector, enter the exact same user name).
6. Specify the service account password (if using admin credentials on the connector, enter the exact same password).
7. Check Specify Exchange Web Services URL and specify the URL (example: https://server/EWS/Exchange.asmx).
8. If using Exchange Server, do not check Use Exchange Impersonation. If you are using Office 365, and using impersonation, do check the box.
9. Check Ignore Trust for SSL.
10. Click on Perform Test.
11. Once results are displayed, check the overall result, and also click on Expand All.

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