Today I found out about a cool new trick from Sing - enabling compatibility mode in IIS 7. When creating sites and especially SharePoint sites – new browsers like IE8 may not tolerate standards that have been implemented in web applications a while ago like MOSS and display your UI not the way you have it coded. Fortunately there is a way to force IE7 mode so that your browser will automatically load the page as it was loaded in IE7. An equivalent to you switching to compatibility mode:
This is done right on IIS level. Here is how:
1. Open your IIS and expand the site or directory you’re forcing compatibility on
2. Select Response Headers option
3. Create a new response header with below values, this will instruct IIS to emulate IE7:
That’s it just call an IISRESET and your site will not run under compatibility mode.
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