To verify EWS availability, follow these steps:
- Connect to your EWS URL via a web browser. It is best to perform this from a computer that is not joined to the domain and has access to the internet;
- Enter your admin credentials when prompted;
- After entering credentials, you should see an XML document (also known as a WSDL).
If you see an Outlook Web App (OWA) forms authentication page, you have configured an incorrect authentication method.
Make sure that the EWS virtual directory is protected, using either Basic Authentication and/or Windows Authentication. An OWA protected EWS virtual directory is generally caused by an ISA firewall policy that was configured incorrectly. If you are using ISA, create a new firewall policy for EWS that leverages an authentication method other than Forms Authentication.
If Forms Authentication is turned on alongside Windows Authentication, you may get the following errors:
- The remote server returned an error: (404) Not Found
- 401 - Unauthorized: Access is denied due to invalid credentials
Disable Forms Authentication and retry. You may need to do an IISreset if the settings do not refresh.