It's caused by the same thing (compatibility mode)
Found this in the Supported Platforms fro 7.7.2 pdf which makes sense
Supported browsers:
- Microsoft Internet Explorer 7, 8, 9, 10, or 11
NOTE: Internet Explorer 7 is not supported for any design or administration functions in Service Desk: you
cannot log in to Web Desk using Internet Explorer 7. End user functions in Self Service are supported, but calendar
functions are not supported. You cannot use Mobile Self Service.
It's going to be another one of those situations whereby you need compatibility mode for some intranet sites but not others. I think that we may have to go for a "use anther browser" approach
Thanks folks