server controls

Hello all,

 I am new asp.net.i am getting below error . Cound any one hep me, thks in advance.

 my code:

<html>
<body>
<form id="f" runat="server">
<span id="s1" runat="server">
</span>
<br>
<input type=button id="b1" runat="server" value="click" onserverclick="m1">
</form>
<script language="vb" runat="server">
sub m1( s as object, e as eventargs)
s1.innerhtml="button click"
end sub
</script>
</body>
</html>

 

when i ran this progrm , i am getting in browser  button with 'click' text, if i click on that  innerhtml is not changing,

means my M1 function is not working.

Could any one help me.

 
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