RadControls for ASP.NET AJAX 
SYMPTOMS
When you try click the Select button of
RadUpload it doesn't work, or you need to click
somewhere else in order to bring the browser dialog.
CAUSE
The TextBox is wider or shorter than the text area of the
File Input, or the Button is wider or
shorter than the button area of the File Input.
RESOLUTION
Follow the instructions for changing file input width in
File Input Appearance or set the
EnableFileInputSkinning property to false.
In addition, check if you have the DocType set in your page:
CopyASPX
<pre xmlns="http://ddue.schemas.microsoft.com/authoring/2003/5">
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
</pre>
See Also