<div>
What should be the reference to choose? Thanks
</div>


<div>
Show the screenshot of your References in Solution Explorer.<br />
Also send the Default.aspx.designer.cs page.
</div>


<div>
Sorry, after I added these<br />

<pre><code class="code-10 nolinks" id="code-20-41482008-1"><span>&lt;ASPP:PopupPanel HeaderText=&quot;This is Header&quot; ID=&quot;pup&quot; </span>
<span>          runat=&quot;server&quot; OnCloseWindowClick=&quot;MycloseWindow&quot;&gt;</span>
<span>    &lt;PopupWindow runat=&quot;server&quot;&gt;</span>
<span>        &lt;ASPP:PopupWindow ID=&quot;PopupWindow1&quot; </span>
<span>        Visible=&quot;false&quot; runat=&quot;server&quot;&gt;</span>
<span>            &lt;asp:Label ID=&quot;lbl&quot; runat=&quot;server&quot;&gt;ssssssssss&lt;/asp:Label&gt;</span>
<span>            &lt;br /&gt;</span>
<span>            &lt;asp:TextBox ID=&quot;txt&quot; AutoPostBack=&quot;true&quot; </span>
<span>            runat=&quot;server&quot;&gt;&lt;/asp:TextBox&gt;</span>
<span>        &lt;/ASPP:PopupWindow&gt;</span>
<span>        &lt;ASPP:PopupWindow ID=&quot;PopupWindow2&quot; runat=&quot;server&quot;&gt;</span>
<span>            &lt;div align=&quot;center&quot; style=&quot;width: 500px; height: 300px&quot;&gt;</span>
<span>                &lt;asp:Label ID=&quot;Label1&quot; runat=&quot;server&quot;&gt;nnnnn&lt;/asp:Label&gt;</span>
<span>                &lt;br /&gt;</span>
<span>                &lt;asp:TextBox ID=&quot;TextBox1&quot; AutoPostBack=&quot;true&quot; </span>
<span>                runat=&quot;server&quot;&gt;&lt;/asp:TextBox&gt;</span>
<span>                &lt;asp:Button ID=&quot;in&quot; runat=&quot;server&quot; Text=&quot;sss&quot; /&gt;</span>
<span>                &lt;asp:TextBox ID=&quot;TextBox2&quot; AutoPostBack=&quot;true&quot; </span>
<span>                runat=&quot;server&quot;&gt;&lt;/asp:TextBox&gt;</span>
<span>            &lt;/div&gt;</span>
<span>        &lt;/ASPP:PopupWindow&gt;</span>
<span>    &lt;/PopupWindow&gt;</span>
<span>&lt;/ASPP:PopupPanel&gt;</span>
</code></pre>
to the Web-page, I then got the problem. Why?
</div>


<div>
Before this, everything is fine.
</div>


<div>
it's not aspp but asp you shouldn't mix classic asp with asp.net
</div>


ASP.Web.UI.PopupControl.txt

<div>
Thanks.<br />
<br />
I've added that dll file into Reference of the project like<br />
<a href="https://app.box.com/s/j808pqjlhgtfl5qvlzf8g6y2gmg6ii4d" rel="ugc">https://app.box.com/s/j808pqjlhgtfl5qvlzf8g6y2gmg6ii4d</a><br />
<br />
but I've still got this<br />
<br />

<pre><code class="code-10 nolinks" id="code-20-41484816-1"><span>Server Error in '/Start3' Application.</span>
<span></span>
<span>Parser Error </span>
<span>  Description: An error occurred during the parsing of a resource required to service this request. Please review the following specific parse error details and modify your source file appropriately. </span>
<span></span>
<span> Parser Error Message: Could not load file or assembly 'ASP.Web.UI.PopupControl' or one of its dependencies. The system cannot find the file specified.</span>
<span></span>
<span>Source Error: </span>
<span></span>
<span></span>
<span></span>
<span>Line 1:  &lt;%@ Page Language=&quot;C#&quot; AutoEventWireup=&quot;true&quot; CodeBehind=&quot;Default.aspx.cs&quot; Inherits=&quot;Start._Default&quot; %&gt;</span>
<span>Line 2:  &lt;%@ Register Assembly=&quot;ASP.Web.UI.PopupControl&quot; </span>
<span>Line 3:      Namespace=&quot;ASP.Web.UI.PopupControl&quot;</span>
<span>Line 4:      TagPrefix=&quot;ASPP&quot; %&gt;  </span>
<span>  </span>
<span></span>
<span> Source File:  /Start3/Default.aspx    Line:  2 </span>
<span></span>
<span>Assembly Load Trace: The following information can be helpful to determine why the assembly 'ASP.Web.UI.PopupControl' could not be loaded.</span>
<span></span>
<span></span>
<span></span>
<span>WRN: Assembly binding logging is turned OFF.</span>
<span>To enable assembly bind failure logging, set the registry value [HKLM\Software\Microsoft\Fusion!EnableLog] (DWORD) to 1.</span>
<span>Note: There is some performance penalty associated with assembly bind failure logging.</span>
<span>To turn this feature off, remove the registry value [HKLM\Software\Microsoft\Fusion!EnableLog].</span>
<span></span>
<span>  </span>
<span></span>
<span></span>
<span>Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.34249  </span>
</code></pre>
<br />
why?
</div>


<div>
Have you added a reference in the project ? <br />
<br />
Currently your app.box.com link is not accessible for me. &nbsp;What you have sent ?
</div>


<div>
Here is the same file<br />
<a href="https://filedb.experts-exchange.com/incoming/2016/02_w10/1084129/tt487.png" target="_blank" title="tt487.png (13 KB)"><img alt="tt487.png" class="file-block lazyload" style="max-width: 768px;" data-src="https://filedb.experts-exchange.com/incoming/2016/02_w10/1084129/tt487.png" /></a><br />
In above, I did already added the DLL file but I'm still getting the problem after having done this.
</div>


tt487.png

<div>
Is it possible for you to share your project sample ?
</div>


<div>
Can I have your email address? Thanks.
</div>


<div>
Its my pleasure to be in touch with you. But sharing an email addresses is not allowed here.<br />
And I think, you can not send DLL files in mail <br />
You upload it on app.box.com &nbsp;and send a link.
</div>


<div>
Can you please refer to this<br />
<br />
<a href="https://app.box.com/s/2orckj9zohsq8xpn55ukx098u429r243" rel="ugc">https://app.box.com/s/2orckj9zohsq8xpn55ukx098u429r243</a><br />
<br />
? Thanks
</div>


<div>
Hi,<br />
<br />
I have seen your sample project. But I didn't get any error or warning.<br />
It runs directly without any error.
</div>


<div>
<div class="content wysiwyg-content">
Hi,<br />
How to resolve these problems?<br />

<pre><code class="code-1 nolinks" id="code-10-28929078-1"><span>Error	15	The type or namespace name 'ASP' could not be found in the global namespace (are you missing an assembly reference?)	C:\App2\Start\Default.aspx.designer.cs	76	27	Start</span>
<span>Error	16	The type or namespace name 'ASP' could not be found in the global namespace (are you missing an assembly reference?)	C:\App2\Start\Default.aspx.designer.cs	85	27	Start</span>
<span>Error	17	The type or namespace name 'ASP' could not be found in the global namespace (are you missing an assembly reference?)	C:\App2\Start\Default.aspx.designer.cs	112	27	Start</span>
</code></pre>
</div>
</div>


Hi,
How to resolve these problems?
(CODE)

Problem with namespace

The successor to Active Server Pages, ASP.NET websites utilize the .NET framework to produce dynamic, data and content-driven web applications and services. ASP.NET code can be written using any .NET supported language. As of 2009, ASP.NET can also apply the Model-View-Controller (MVC) pattern to web applications

ASP.NET

The .NET Framework is not specific to any one programming language; rather, it includes a library of functions that allows developers to rapidly build applications. Several supported languages include C#, VB.NET, C++ or ASP.NET.

.NET Programming

C# is an object-oriented programming language created in conjunction with Microsoft’s .NET framework. Compilation is usually done into the Microsoft Intermediate Language (MSIL), which is then JIT-compiled to native code (and cached) during execution in the Common Language Runtime (CLR).

Extensible Markup Language (XML) refers to the encoding of documents such that they can be read by both machines and humans. XML documents use tags to show the beginning and end of a set of data. XML is used extensively on websites to show volumes of data, and is the default for a number of office productivity suites. This topic includes discussions of XML-related technologies, such as XQuery (the XML Query language), XPath (the XML Path language), XSLT (eXtensible Stylesheet Language Transformations), XLink (the XML Linking language) and XPointer (the XML Pointer language).

A scripting language is a programming language that supports scripts, programs written for a special run-time environment that automate the execution of tasks that could alternatively be executed one-by-one by a human operator. Scripting languages are often interpreted (rather than compiled). Primitives are usually the elementary tasks or API calls, and the language allows them to be combined into more complex programs. Environments that can be automated through scripting include software applications, web pages within a web browser, the shells of operating systems (OS), embedded systems, as well as numerous games. A scripting language can be viewed as a domain-specific language for a particular environment; in the case of scripting an application, this is also known as an extension language.