I am wondering how do you stop people who are using IE 8 from going to Compatibility mode?
<meta http-equiv="X-UA-Compatible" content="IE=8" />
I found this tag and I think this forces people to stay in IE-8 mode but I am not too sure and can't check as I have IE 9.
If people are in IE 9 mode I force them to not go into IE 8 or IE 7 Compatibility mode?
I tried to put the above line in my code and went to IE 9 -> Tools -> Compatibility View(Grayed Out)
but "Compatibility View Settings" was not grayed out and it seems you could add the site through there.
So should that not disable?
All you need is to force disable C.M. in IE - Just paste This code (in IE9 and under c.m. will be disabled):
<meta http-equiv="X-UA-Compatible" content="IE=9; IE=8; IE=7; IE=EDGE" />
Source: http://twigstechtips.blogspot.com/2010/03/css-ie8-meta-tag-to-disable.html