When Internet Explorer Security settings are set to "High", Active Scripting will be automatically disabled.
MailGate needs this option enabled in order to display the secure email content properly, otherwise, the user will get a blank page

Possible solutions:
- Lower the Internet Security settings from "High" to "Medium-High"
- Add the secure messenger page to the Trusted Sites zone, where normally the security level is lower than the one for the Internet zone
- Click on Settings > Internet Options > Security > Internet Zone > Custom Level and scroll down to "Active Scripting". Switch the radio button to "Enabled"