FIX: "COM Object Can Not Be Used" Error Message When You Use an STA COM Object That You Created by Using Server.CreateObject and Stored in Session Scope in a Different Web Page

You create a single-threaded apartment (STA) COM object by using Server.CreateObject, and then you store this STA COM object in session scope. If you use this STA COM object from another Web page, you receive the following error message:

Important To apply this hotfix, you must have the .NET Framework Service Pack 2 installed.

How to obtain the hotfix

This issue is fixed in the June 2003 ASP.NET Hotfix Package 1.1. For additional information, click the following article number to view the article in the Microsoft Knowledge Base: You cannot obtain this fix individually. You must install the rollup.

Note When you request this hotfix, you receive the rollup.

The English version of this hotfix has the file attributes (or later) that are listed in the following table. The dates and times for these files are listed in coordinated universal time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time tool in Control Panel.
This hotfix is also available for the German version of the Microsoft .NET Framework 1.0. This hotfix is also available for the French version of the Microsoft .NET Framework 1.0.

If you applied the hotfix in this article for Microsoft ASP.NET included with the .NET Framework 1.0, and if you upgraded to Microsoft ASP.NET included with the .NET Framework 1.1, apply the hotfix package from the following Microsoft Knowledge Base article: Additionally, if you upgraded to the .NET Framework 1.1, and if you experience the symptoms in this article, apply the hotfix package from this Microsoft Knowledge Base article.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

If you create an STA object by using Server.CreateObject (Attribute AspCompat ="true"), you can use the object only in the Web page that you created it for. If you store the object in session scope, and then you try to gain access to it from a different Web page, you receive the error message.

Additionally, if you implement the OnStartPage method and the OnEndPage method from your STA COM object, these methods are not called on your object in the second Web page.

Steps to reproduce the behavior

1. Use the following sample code to create a Microsoft Visual Basic 6.0 COM object that has AspEventProblem.Class1 for the ProgId:

   Public Function Test() As String
          Test = "Hello from COM Object"
   End Function

2. Use Microsoft Visual Basic .NET to create a new Web application.
3. Create a Web Form named WebForm1.aspx.
4. Add a Button object to WebForm1.aspx that contains the following sample code:

   Private Sub Page_Load(ByVal sender As System.Object, ByVal e As 	System.EventArgs) Handles MyBase.Load 
         Session("mycomp") =Server.CreateObject("AspEventProblem.Class1") 
   End Sub Private Sub
   Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
         Handles Button1.Click Response.Redirect("webform2.aspx") 
   End Sub 

5. Create a Web Form named WebForm2.aspx that contains the following sample code:

   Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
           Label1.Text = Session("mycomp").Test()
   End Sub

6. In your browser, view WebForm1, and then click Button1.
7. When WebForm2 appears, click Button1.