Hello,

i have publish on file for you you can see how look that on chrome, IE10 and opera for example and ofcourse on IE11 or Firefox 25.0.1.

<%@ Page Title="" Language="C#" MasterPageFile="~/Page.Master" AutoEventWireup="true" CodeBehind="WebFileUploader.aspx.cs" Inherits="StudioSystem.TempReports.WebFileUploader" %>
<%@ Register assembly="ISNet.WebUI.WebCombo" namespace="ISNet.WebUI.WebCombo" tagprefix="ISWebCombo" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="server">
    <ISWebCombo:WebCombo ID="WebCombo1" runat="server" DataSourceID="SqlDataSource1" DataTextField="OPIS" DataValueField="KOD" Height="20px" UseDefaultStyle="True" Width="200px" RenderingMode="HTML5">
</ISWebCombo:WebCombo>
<asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:StudioSystemConnectionString %>" SelectCommand="SELECT [KOD], [OPIS] FROM [x_skorowidze] WHERE ([PRX] = @PRX)">
    <SelectParameters>
        <asp:Parameter DefaultValue="MAG" Name="PRX" Type="String" />
    </SelectParameters>
</asp:SqlDataSource>
    <ISWebCombo:WebCombo ID="WebCombo2" runat="server" UseDefaultStyle="true">
    </ISWebCombo:WebCombo> 
    </asp:Content>

Sample site

http://studiosystem.demo.softwarestudio.com.pl/TempReports/WebCombo.aspx

Please look on that. Meaybe that help you to resolve this problem. 

Thank you.

Regards,
Adam

Hi Hans,

Unfortunately, the change to HTML5 doctype and set RenderingMode property in WebExplorerPane according to your example did not help.

I tried to run as your aspx file, also received the same error as before.

Can you have any idea how to get rid of this error?

Thank you for your answer.

Regards,

Przemysław.

HI, Hans.

Thank you for your reply and sample source code.

My error message but still pops up.

I attach error.png image, this is JavaScript error screenshot from your .aspx file in my Visual Studio.

Regards, Przemysław.