The problem is that the javascript is assuming that the button really is named Button3... which in a regular page it would be, but in case of a module (or anything in "containers" or master pages for example), it isn't.  It is really going to be something funky like dnn_ctrl123_button3 and the way to find that is to (in VB or C# code behind, use Button3.ClientID).  So how do you get that to output into your javascript?  Have a function within your codebehind like "PopulateScript" or something creative like that and then use a StringBuilder or other string method to build your javascript function and in place of 'Button3' put Button3.ClientID which will output the unique clientside id that will be generated for that button.  Then at the end of building your script call Page.RegisterStartupScript (I can't remember the exact call off the top of my head and not on a computer with Visual Studio on it) and it'll insert your function into the page.

Hopefully that helps... if not I'll be on a computer with some code tomorrow and can post up a snippet (or somebody else may have answered with a snippet by then).

Thank you for the response it helped a lot.  Problem solved my solution was a little different then what you posted but along the same lines

Dim

myScript As String = "function facIDSelect(){ document.getElementById('" & Button3.ClientID & "').focus(); }"

Page.ClientScript.RegisterClientScriptBlock(Page.GetType,

"ScriptFunction", myScript, True)

Thanks for your help

Mike