I have spent the last day reformatting pages as they were not displaying as intended in IE8 (mainly issues with centering and changing to margin: 0 auto 0 auto; for divs/tables).

Once finished, before putting the new aspx pages onto our test servers, I was doing another quick bug fix and noticed that the pages were actually displayed with the correct formatting (as set up for IE6/IE7) on our test servers.

After seeing this I then went back to my locally hosted files and noticed that when calling the localhost/127.0.0.1 the pages displayed incorrectly, but when I used my local server name/ip address the pages were formatted as intended. e.g.

//localhost/mainpage.aspx - page format incorrect

//withnail/mainpage.aspx - page formatted correctly

Just wondering if there is a explanation for this, or a work around to get the page displaying correctly no matter how it is called? (Would be nice to know the reason why, rather than just ignore it)

This might be because of "compatibility" mode. IE may enable compatibility mode if it thinks the page needs it. So, it might be turning off compatibility on for http://localhost, but turning it on for http://mytestserver. Check and see if it is enabled. It's the picture of the torn document next to the address bar.

withnail:

Just wondering if there is a explanation for this, or a work around to get the page displaying correctly no matter how it is called? (Would be nice to know the reason why, rather than just ignore it)

This is because Browser Compatible issue.  so you have to check it on both browser. Try to apply all the styles on CSS.

vcsjones, you've nailed it.

When compatibility view is enabled or set to "Display all websites in compatibility view" rather than just intranet sites, the page is rendered as it would on IE6/7.

Cheers for the help.