How to remove IE8 compatibility button in asp.net?

Put following code BEFORE header:
<!--[if gte IE 7]><meta http-equiv="X-UA-Compatible" content="IE=8"/> <![endif]-->

How to make label in asp.net text-wrap

Add a div following to wrap your label:

<div style="overflow-y:auto;overflow-x:auto; word-break:break-all;" runat="server">