asp.net button has to be clicked twice

[asjc]

For some reason whenever I use an asp button it must be clicked twice before the searchButton_Click function is called successfully.

<asp:button id=&quot;SearchButton&quot; onclick=&quot;SearchButton_Click&quot; BorderColor=&quot;RoyalBlue&quot; runat=&quot;server&quot; Text=&quot;Search&quot; Height=&quot;20px&quot; Font-Size=&quot;8pt&quot; Font-Name=&quot;Verdana&quot; Font-Bold=&quot;True&quot;></asp:button>

Can anyone help me so that is works when clicked just once.
yours annoyingly
adam