Incomplete URL content displayed through Clientless VPN.
8282
Created On 10/01/19 21:36 PM - Last Modified 02/03/26 14:44 PM
Symptom
- Site content not displaying through Clientless VPN with Internet Explorer version 11(IE11).
- Site content shows up completely when access directly from same browser IE11 without Clientless VPN.
- Only IE browser is working to access the site application.
- Other browser such as Chrome is not working when accessing the site with and without Clientless VPN.
Environment
- PAN-OS versions 8.0 and above
- Browser: Internet Explorer 11 and above (IE11+)
- Clientless VPN
Cause
- The site content was written to conform to the Web Standard for version Internet Explorer 7 (IE7).
- The application on the server had enforced "X-UA-Compatible: IE=EmulateIE7 to render the display to work with newer IE versions.
- Clientless VPN is not compatible with IE7 and/or 'X-UA-Compatible: IE=EmulateIE7' and unable to display the content in IE.
Resolution
The resolution for this problem is to rewrite the content of the website to be comply with the newer browser standards.
Clientless VPN is not compatible with older browsers such as IE7 and supports most modern browsers' latest versions for Chrome, Internet Explorer, Firefox and Safari.
Clientless VPN is working as expected.
Additional Information
HTTP response header without clientless VPN captured using Fiddler displays Emulated IE7
This confirms the application enforcing X-UA-Compatible: IE=EmulateIE7 mode to make it compatible with latest IE browsers.
For additional details of X-UA-Compatibility tag, check the Microsoft link.