I just configured a Sophos UTM cluster based on software version 9. I was able to configure the appliance via WebAdmin and I could access the User Portal without any problems. The customer is using a Citrix based environment with Internet Explorer 9. IE9 is configured to use the Sophos UTM cluster as proxy server. The customer was able to access the User Portal, but he couldn’t access the WebAdmin page.
When they tried to access the WebAdmin page, the page isn’t shown correctly. The page is crippled and you don’t get the login options for entering username and password. We tried different settings, like adding the page to the trusted websites and to the proxy exemptions. Nothing seemed to help. We asked mighty Google for help and we found the following thread.
The following snippet from the thread solved the problem:
Had one of my guys have this problem already… remove the URL for the UTM from the Compatibility View list (in his case, he had to uncheck the “view intranet sites in compatibility view” checkbox in IE).
The customer changed this Group Policy Object in Active Directory and everybody was happy.