Follow these instructions to target specific versions of Internet Explorer:
Targeting ALL VERSIONS of IE
<!--[if IE]>
<link rel="stylesheet" type="text/css" href="all-ie-only.css" />
<![endif]-->
Exclude targeting IE
<!--[if !IE]><!-->
<link rel="stylesheet" type="text/css" href="not-ie.css" />
<!--<![endif]-->
Target ONLY IE 7
<!--[if IE 7]>
<link rel="stylesheet" type="text/css" href="ie7.css">
<![endif]-->
Target ONLY IE 6
<!--[if IE 6]>
<link rel="stylesheet" type="text/css" href="ie6.css" />
<![endif]-->
Target ONLY IE 5
<!--[if IE 5]>
<link rel="stylesheet" type="text/css" href="ie5.css" />
<![endif]-->
Target ONLY IE 5.5
<!--[if IE 5.5000]>
<link rel="stylesheet" type="text/css" href="ie55.css" />
<![endif]-->
Target IE 6 and LOWER
<!--[if lt IE 7]>
<link rel="stylesheet" type="text/css" href="ie6-and-down.css" />
<![endif]-->
<!--[if lte IE 6]>
<link rel="stylesheet" type="text/css" href="ie6-and-down.css" />
<![endif]-->
Target IE 7 and LOWER
<!--[if lt IE 8]>
<link rel="stylesheet" type="text/css" href="ie7-and-down.css" />
<![endif]-->
<!--[if lte IE 7]>
<link rel="stylesheet" type="text/css" href="ie7-and-down.css" />
<![endif]-->
Target IE 8 and LOWER
<!--[if lt IE 9]>
<link rel="stylesheet" type="text/css" href="ie8-and-down.css" />
<![endif]-->
<!--[if lte IE 8]>
<link rel="stylesheet" type="text/css" href="ie8-and-down.css" />
<![endif]-->
Target IE 6 and HIGHER
<!--[if gt IE 5.5]>
<link rel="stylesheet" type="text/css" href="ie6-and-up.css" />
<![endif]-->
<!--[if gte IE 6]>
<link rel="stylesheet" type="text/css" href="ie6-and-up.css" />
<![endif]-->
Target IE 7 and HIGHER
<!--[if gt IE 6]>
<link rel="stylesheet" type="text/css" href="ie7-and-up.css" />
<![endif]-->
<!--[if gte IE 7]>
<link rel="stylesheet" type="text/css" href="ie7-and-up.css" />
<![endif]-->
Target IE 8 and HIGHER
<!--[if gt IE 7]>
<link rel="stylesheet" type="text/css" href="ie8-and-up.css" />
<![endif]-->
<!--[if gte IE 8]>
<link rel="stylesheet" type="text/css" href="ie8-and-up.css" />
<![endif]-->