Refer to below Citrix KB article:
http://support.citrix.com/article/CTX128789
Or follow these steps:
1. In Windows Taskbar, click on the Server Manager icon or click Run and type ServerManager.msc.
2. Scroll down to the Security Information section.
3. Click 'Configure IE ESC-Icon' option located towards right side of screen.
4. A new dialog that allows to adjust the Configuration for Administrators and Users appears with IE Explorer Enhanced Security Configuration option turned off. Click OK on this dialog.
5. Click Run from Windows Start menu and type the following text:
“C:\Windows\system32\rundll32.exe” C:\Windows\system32\iesetup.dll,IEShowHardeningDialog
6. A new dialog that allows to adjust the Configuration for Administrators and Users appears with IE Explorer Enhanced Security Configuration option turned off. Click OK on this dialog.
