I have a page that when auto or partial post back happens, focus is set to the address bar rather than the next control. The interesting thing is that when I put an alert in my RadScriptBlock, after the OK is clicked, focus goes to the correct control -or- if I put in an invalid location, focus is returned to the ExpLocation control & when a correct location is input the second time, the tab order/focus command works correctly (see code below).

That has this up top

<telerik:RadAjaxManager ID="RadAjaxManager1" runat="server">
    <AjaxSettings>
        <telerik:AjaxSetting AjaxControlID="RadAjaxPanel1">
            <UpdatedControls>
                <telerik:AjaxUpdatedControl ControlID="RadAjaxPanel1" LoadingPanelID="RadAjaxLoadingPanel1" />
            </UpdatedControls>
        </telerik:AjaxSetting>
        <telerik:AjaxSetting EventName="OnTextChanged" AjaxControlID="RadNumericTextBox_GLm">
            <UpdatedControls>
                <telerik:AjaxUpdatedControl ControlID="RadNumericTextBox_GLm" LoadingPanelID="RadAjaxLoadingPanel1" />
                <telerik:AjaxUpdatedControl ControlID="lblGlCodeErrorMessage" LoadingPanelID="RadAjaxLoadingPanel1" />
            </UpdatedControls>
        </telerik:AjaxSetting>
        <telerik:AjaxSetting EventName="OnTextChanged" AjaxControlID="RadNumericTextBox_ExpLocation">
            <UpdatedControls>
               <telerik:AjaxUpdatedControl ControlID="lblGlCodeErrorMessage" LoadingPanelID="RadAjaxLoadingPanel1" />
                <telerik:AjaxUpdatedControl ControlID="RadNumericTextBox_ExpLocation" LoadingPanelID="RadAjaxLoadingPanel1" />
            </UpdatedControls>
        </telerik:AjaxSetting>
    </AjaxSettings>
</telerik:RadAjaxManager>

<telerik:RadNumericTextBox ID="RadNumericTextBox_ExpLocation" runat="server" Width="20px" AutoPostBack="true"
MaxLength="3" NumberFormat-AllowRounding="False" Type="Number" NumberFormat-KeepTrailingZerosOnFocus="True"
IncrementSettings-InterceptMouseWheel="false" OnTextChanged="LocationCheck_OnTextChanged" TabIndex="101">
<NumberFormat DecimalDigits="0" GroupSeparator="" AllowRounding="false" KeepNotRoundedValue="false" />

 protected void LocationCheck_OnTextChanged(object sender, System.EventArgs e)
{
    var cmdText = "SELECT LMLOC FROM DBMOTO..XALOCNP WHERE  " +
            " LMLOC = @ExpLocation ";
        using (var conn = new SqlConnection(ConfigurationManager.ConnectionStrings["MAINConnectionString"].ToString()))
        using (var cmd = new SqlCommand(cmdText, conn))
        {
            cmd.Parameters.Add(new SqlParameter("@ExpLocation", RadNumericTextBox_ExpLocation.Text));
            conn.Open();
            SqlDataReader dr = cmd.ExecuteReader();
            if (dr.HasRows)
            {
                Session["ValidGL"] = false;
                lblGlCodeErrorMessage.Visible = false;
                lblGlCodeErrorMessage.Text = "Good Location";
                btnAddItem.Enabled = false;
                btnDone.Enabled = false;
                RadNumericTextBox_GLm.Focus();
            }
            else
            {
                lblGlCodeErrorMessage.Visible = true;
                lblGlCodeErrorMessage.Text = "Invalid/Inactive Location";
                btnAddItem.Enabled = false;
                btnDone.Enabled = false;
                RadNumericTextBox_ExpLocation.Focus();
            }
        }
}