Fix Exchange ActiveSync Fails After Updating an Exchange 2007 Certificate
Question details
Mobile devices are unable to connect to Exchange ActiveSync after updating the Exchange 2007 SSL certificate, despite successful network and certificate validation tests.
- Product
- Microsoft Exchange Server 2007
- Device & OS
- not provided
- Scenario
- Administrators updating or replacing the SSL certificate on an Exchange 2007 server to maintain secure mobile connections.
- Observed behavior
- ActiveSync connections fail during the HTTP authentication step. DNS resolution, port 443 connectivity, and SSL certificate validation succeed, but the HTTP request fails because anonymous authentication alone is not supported.
Ensure you have administrative access to the Exchange Server and IIS Manager, and verify that your new SSL certificate has been properly imported into the server's certificate store.
Configure IIS Authentication for the ActiveSync Virtual Directory
Ensure the new certificate is properly assigned and the ActiveSync virtual directory is configured with the correct authentication methods, as Anonymous access alone is insufficient.
When an SSL certificate is replaced, IIS settings or virtual directory configurations for Exchange ActiveSync can sometimes reset or become misaligned. ActiveSync requires specific authentication methods (typically Basic Authentication) to process mobile device credentials securely.
Relying solely on Anonymous authentication will cause HTTP authentication failures during connectivity tests.
Log in to your Exchange Server, open the Start menu, navigate to Administrative Tools, and launch Internet Information Services (IIS) Manager.
Expand your server node, click on 'Sites', and select 'Default Web Site'. Click 'Bindings' in the right-hand Actions pane. Select 'https' (port 443), click 'Edit', and ensure your newly installed SSL certificate is selected from the SSL certificate drop-down menu.
Under the Default Web Site, locate and click on the 'Microsoft-Server-ActiveSync' virtual directory.
In the middle pane, double-click 'Authentication'. Ensure that 'Basic Authentication' is set to Enabled. If 'Anonymous Authentication' is enabled, ensure it is not the only active method, as ActiveSync requires Basic Authentication to function correctly.
Open an elevated Command Prompt and type 'iisreset', then press Enter to apply the new authentication and binding settings.
Test Connection Using Microsoft Remote Connectivity Analyzer
Use Microsoft's official diagnostic tool to pinpoint exactly where the ActiveSync authentication process is failing.
Need a Reliable Office Suite for Your Business?
While managing Exchange Server configurations requires specialized administrative tools, your daily business tasks require a robust and accessible office suite. WPS Office provides a lightweight, fully compatible alternative to Microsoft Office for all your document, spreadsheet, and presentation needs.
- 1. Download the Installer: Visit the official WPS Office website and click the free download button for your operating system.
- 2. Install WPS Office: Run the downloaded setup file and follow the quick, lightweight installation process.
- 3. Open Your Documents: Launch WPS Office and instantly open your existing Microsoft Office files without losing any formatting.
Frequently Asked Questions
Why does Exchange ActiveSync fail even when the SSL certificate is valid?
ActiveSync can fail if the IIS virtual directory lacks the correct authentication methods. Even if the certificate is perfectly valid and trusted, missing Basic Authentication settings will result in an HTTP 401 Unauthorized error because the server cannot securely process the user's credentials.
Can I use only Anonymous authentication for Exchange ActiveSync?
No, Anonymous authentication alone is not supported for Exchange ActiveSync. While the initial HTTPS request might succeed anonymously, the actual synchronization process requires methods like Basic Authentication or Client Certificate authentication to verify the user's identity.
How do I know if my new Exchange certificate is bound to IIS correctly?
You can verify the binding by opening IIS Manager, selecting your 'Default Web Site', and clicking 'Bindings' in the Actions pane. Check the HTTPS binding on port 443 to ensure your newly installed certificate is explicitly selected in the drop-down menu.
Will restarting IIS disconnect current Outlook users?
Yes, running the 'iisreset' command will briefly interrupt web services, including Outlook Anywhere (RPC over HTTP) and Outlook on the Web (OWA) users. It is recommended to perform IIS restarts during a maintenance window or periods of low user activity.
