Return argument has an invalid type

10. December 2009 07:39 by Mrojas in General  //  Tags: , , , , ,   //   Comments (0)

When you develop applications with remoting, or in some COM + Remoting scenarios, you could start founding very interesting exceptions.

We had a very unconfortable one. We had an ActiveX that is used in an intranet Web Page, that uses remoting to instanciate some classes in the local network.

When we runned outside of the IE, everything seem to work, but running in IE it produced an exception like:

Error : Return argument has an invalid type.
Type  : System.InvalidCastException
Source: mscorlib
Source: at System.Runtime.Remoting.Proxies.RealProxy.ValidateReturnArg(Object arg, Type paramType)
at System.Runtime.Remoting.Proxies.RealProxy.PropagateOutParameters(IMessage msg, Object[] outArgs, Object returnValue)
at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)

Why??? Well what happens is simple, it is having an assembly resolution problem, it is not being able to resolve the type.

We solve the problem adding something like:

1. Find a place in your code to add an event like this (it could be in the Main of your program for example):

AppDomain.CurrentDomain.AssemblyResolve += new ResolveEventHandler(CurrentDomain_AssemblyResolve);
2. Add a handler like this: 

static System.Reflection.Assembly CurrentDomain_AssemblyResolve(object sender, ResolveEventArgs args)
System.Reflection.Assembly assembly = null; 
assembly = System.Reflection.Assembly.Load(new System.Reflection.AssemblyName(args.Name));
   catch (Exception ex)
            string.Format(“Problem with resolution of {0} : {1} {2}”, args.Name, ex.Message, ex.StackTrace));
   return assembly;

Well, this worked for us, and I hope that helps you out.


Code compiles but System.IO.FileNotFound Exception is thrown

2. October 2009 10:04 by Mrojas in General  //  Tags: , , , , , , ,   //   Comments (0)

We have seen a situation that can be a little annoying.
I usually find that situation in ASP.NET projects, but it can also happen in Winforms.

The issue is like this:

  • You have a VStudio Solution
  • You have added all the needed references
  • All your code compiles



When you run the application it terminates at a certain point with a
FileNotFound exception indicating that the assembly blablabla  or one of its
dependencies could not be loaded.


Whats hapenning!!!

Do this:

1) Look at the bin\debug or bin\release and make sure that the assembly is in those directories.

2) If the assembly is not there, then go to the project references in the solution explorer, right click and select properties and set the Copy Local Setting



Mapping VBRUN.RasterOpConstants

1. October 2009 05:44 by Mrojas in General  //  Tags: , , , , ,   //   Comments (0)


vb Constant Decimal Value Hex Value .NET
vbDstInvert 5570569 H550009
vbMergeCopy 12583114 HC000CA
vbMergePaint 12255782 HBB0226
vbNotSrcCopy 3342344 H330008
vbNotSrcErase 1114278 H1100A6
vbPatCopy 15728673 HF00021
vbPatInvert 5898313 H5A0049
vbPatPaint 16452105 HFB0A09
vbSrcAnd 8913094 H8800C6
vbSrcCopy 13369376 HCC0020
vbSrcErase 4457256 H440328
vbSrcInvert 6684742 H660046
vbSrcPaint 15597702 HEE0086

IE Explorer and Favorites folder or Special Folders in general

29. September 2009 04:05 by Mrojas in General  //  Tags: , , , , , ,   //   Comments (0)

I found this email in my inbox today:

Hi Mauricio,I came across a reference to your blog at :

I have been studying your writings on extending the WebBrowser control, and verified that the extended web code you wrote for C# compiles and works fine in VS 2010 beta, against FrameWork 4.0.

Many thanks for the valuble code and writing !

I am "stuck" on how to read the contents of an IE browser page when the page is displaying a local file, like the contents of the Favorites folder.

All my attempts to get at the Document or DomDocument by casting it to the usual mshtml.dll interfaces fail.

I am NOT asking you to answer my question, or respond, but if you ever get interested in blogging about this aspect of use of IE, I think many people would be interested.

I have done a lot of research on the net, and posted my own question on StackOverFlow : so far not one real pointer, and, possibly, this is not "doable" (?) : maybe what you are seeing when IE shows a file contents is a kind of "virtual explorer" view that is not parseable.

best, Bill xxxxxx”

And I decided to take at look at it to see if I could be of any help and I found out that it is easy and doable.

So I find an useful link by Andreas M. if you want to look at it.

In general My Favorites, Desktop, etc are special folder. So they need a trick to be able to access them.



Take the code from my ExtendedWebBrowser sample published in

and and

1. Add a reference to %windir%\system32\shell32.dll

2. Add a new property to the ExtendedWebBrowser like:

    /// <summary>
    /// Returns the shell folderview object displayed in the webbrowser control.
    /// </summary>
    public Shell32.IShellFolderViewDual2 FolderView
            return ((SHDocVw.WebBrowser)base.ActiveXInstance).Document
                     as Shell32.IShellFolderViewDual2;

And now you can access the special folder from your code. As Bill mentioned, that “page” or “special page” is not real HTML and not parseable but you can examine its contents for example you can do something like:

        /// <summary>
        /// Button 1_ click
        /// </summary>
        private void button1_Click(object sender, EventArgs e)
            Shell32.IShellFolderViewDual2 specialFolder = this.extendedWebBrowser1.FolderView;
            string folderName = specialFolder.Folder.Title;
            string parentFolder = specialFolder.Folder.ParentFolder.Title;
            foreach (Shell32.ShellFolderItem f in specialFolder.Folder.Items())
                if (f.IsFolder)
                    System.Diagnostics.Debug.WriteLine("Folder:" + f.Name);
                    System.Diagnostics.Debug.WriteLine("File:" + f.Name);
            } // foreach
        } // button1_Click(sender, e)

Using Custom Maps in the VBUC to change class names

28. September 2009 10:28 by Mrojas in General  //  Tags:   //   Comments (0)

The VBUC has a now a nice feature called CustomMaps.This feature allow the users to perform basic customizations in the way the target code is generated.

During migration the VBUC can perform some name changes due to the Keyword restrictions in .NET.

For example  VB.NET the some of the following keywords that cannot be used as class or variable names:

Interface, Alias, And, Class, Error, Friend, Loop, MyBase, MyClass, Shared, Property

See here for a list of all VB.Net keywords.

1. Open the Artinsoft VBUC


2.  Go to the Tools Menu\Custom Maps Editor


The Custom Maps Editor dialog will show up.


3.  In the Custom Maps Editor select New...



4.  Type a name and description for your custom map.


5. Create some Custom Maps lines.

Follow these steps:

a. First type a new SourceName. The source name is used by the VBUC to identify the element that you want to map.
NOTE: If you are migrating just one Project, you just enter one custom maps line with the the source name of the class you want to rename. If your are migrating several project you must enter an additional line like <ProjectName>.<ClassName> for example Project1.Interface that is because for other projects that have Project1 as a Reference they see that class as Project1.Interface and not just Interface.



b. Set the Map Type. For classes we call it a Type Map. For Functions, Subs or Properties we call it a member map.



c. We now change the New Reference Name. For a class we call a “Reference Name” to every time a the class is used to define a variable. For example each Dim x as Class1, or every appearance as a parameter, like Sub Foo(x as Class1).


d. We set the Reference Action to Modify.



e. And we set the NewDeclarationName to InterfaceClass and the DeclarationAction to Modify



f.  To make sure that Keyword renamed declarations are mapped with your custom maps configuration, you have to add a line just the same as the one you had just entered but type Interface_Renamed in the SourceName



6. Now you have to activate it in your profile. Click on the Edit button for profiles in the main VBUC window



7. If you don’t have a Profile now, In the Profile Maintenance Dialog click New, and type a name for your Profile.



8. In your profile Select the custom maps configuration you just created:


9. Now Upgrade all your code.

VB6 Declarations like:


will be migrated as:

Option Strict Off
Option Explicit On
Imports System
Friend Partial Class Form1
    Inherits System.Windows.Forms.Form
    'UPGRADE_WARNING: (2080) Form_Load event was upgraded to Form_Load event and has a new behavior. More Information:
    Private Sub Form1_Load(ByVal eventSender As Object, ByVal eventArgs As EventArgs) Handles MyBase.Load
        Dim y As InterfaceClass
    End Sub
    Sub Foo(ByRef x As InterfaceClass) 

    End Sub
End Class

And the class definition to:

Option Strict Off 
Option Explicit On 
Imports System 
Friend Class InterfaceClass 
End Class

Extended WebBrowser Control Series: WPF WebBrowser and the NewWindow2

To be able to catch popup windows and open them in your own window you
have to manage WebBrowser events like NewWindow2.

But how do you do that in WPF?

Well it isn’t really that difficult. These are the steps that you have to follow:

1. Add a COM reference to a reference to %windir%\system32\shdocvw.dll

2. Add a new CodeFile to your project. Lets say CodeFile1.cs And put this code:

using System;
using System.Runtime.InteropServices;
[ComImport, InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
internal interface IServiceProvider

[return: MarshalAs(UnmanagedType.IUnknown)] 

object QueryService(ref Guid guidService, ref Guid riid);


3. To make an easy example. Lets assume we have a very simple window like:


And in that form we need some code like this:

        private void button1_Click(object sender, RoutedEventArgs e)
            Guid SID_SWebBrowserApp = 
new Guid("0002DF05-0000-0000-C000-000000000046"); IServiceProvider serviceProvider =
(IServiceProvider)myWebBrowser.Document; //<—It seams that you need to
// navigate first to initialize this Guid serviceGuid = SID_SWebBrowserApp; Guid iid = typeof(SHDocVw.IWebBrowser2).GUID; //Here we will get a reference to the IWebBrowser2 interface SHDocVw.IWebBrowser2 myWebBrowser2 =
serviceProvider.QueryService(ref serviceGuid, ref iid);
            //To hook events we just need to do these casts
            SHDocVw.DWebBrowserEvents_Event wbEvents = 
(SHDocVw.DWebBrowserEvents_Event)myWebBrowser2; SHDocVw.DWebBrowserEvents2_Event wbEvents2 =
            //Adding event handlers is now very simple
            wbEvents.NewWindow += 
new SHDocVw.DWebBrowserEvents_NewWindowEventHandler(wbEvents_NewWindow);
            wbEvents2.NewWindow2 += 
new SHDocVw.DWebBrowserEvents2_NewWindow2EventHandler(wbEvents2_NewWindow2); } void wbEvents2_NewWindow2(ref object ppDisp, ref bool Cancel) { //If you want make popup windows to open in your own window
// you need to assign the ppDisp to the .Application of
// the WebBrowser in your window
            Window1 wnd = new Window1();
//Just navigate to make sure .Document is initilialized wnd.myWebBrowser.Navigate(new Uri("about:blank"));
Guid SID_SWebBrowserApp = new Guid("0002DF05-0000-0000-C000-000000000046"); IServiceProvider serviceProvider = (IServiceProvider)wnd.myWebBrowser.Document; Guid serviceGuid = SID_SWebBrowserApp; Guid iid = typeof(SHDocVw.IWebBrowser2).GUID; SHDocVw.IWebBrowser2 myWebBrowser2 = (SHDocVw.IWebBrowser2)serviceProvider.QueryService(ref serviceGuid, ref iid); ppDisp = myWebBrowser2.Application; } void wbEvents_NewWindow(string URL, int Flags, string TargetFrameName, ref object PostData, string Headers, ref bool Processed) { MessageBox.Show(URL); } private void button2_Click(object sender, RoutedEventArgs e) { myWebBrowser.Navigate(new Uri("file://D:/MyProjects/ExtendedBrowserExample_v2/test0.htm")); }

Now you can manage your popupwindows:


You can download the test application from HERE

Continuous Migration with VBUC and MS Team System 2005

22. September 2009 09:59 by Mrojas in General  //  Tags:   //   Comments (0)



Performing Continuous Migration with the Artinsoft VBUC and MS Team System 2005 is simple.

The 4 main tasks are:

1. Configure The Microsoft Visual Studio 2005 to use your desired Team System Project.
          For details…

2. Upload an initial version of your VB6 code to the Source Control system. For details…

          Perform an initial migration an establish a baseline. For details…

3. After that you are all set and you can start doing incremental migration.
          For details and an example of continuos migration…

Continuous Migration VBUC-MS Team System 2005: Start up

22. September 2009 09:45 by Mrojas in General  //  Tags:   //   Comments (0)

Make an initial migration of the VB6 source code

1. Open the VBUC


2. Create a Migration Solution for your code (for example C:\MergeExample\Sample1)


3.  Upgrade your code

4. Open the Explorer and navigate to the location of your VB6 code (For example C:\MergeExample\Sample1)

5. Under the directory where your code is located, create a new directory called GreenCode (For our example this directory will be C:\MergeExample\Sample1\GreenCode )

6. Copy your migrated code to GreenCode (for our example it means copying the contents of C:\MergeExample\Sample1\VB6_UpgradedCode to the C:\MergeExample\Sample1\GreenCode).
All this is important to helps us stablish a base line for comparison and merge

7. Open Microsoft Visual Studio 2005

8. On the Team Explorer locate your project (for example MergeExample) and double click on SourceControl

9. On the Source Control Explorer toolbar click the Add Files button


10. Click the Add Folder… button and select the GreenCode folder we had just created


11. Check in the GreenCode. IMPORTANT. Add a descriptive Comment. We recommed at least setting this information:

  • Green Code Date
  • VB6 Source Code Date/ version
  • VBUC version used to generate the Green Code


    12. Create a brach of the Green Code


    Create a Branch of the GreenCode directory and call it MigratedCode.
    For example in the target field type: $/MergeExample/Sample1/MigratedCode


    After branching you will node a MigratedCode folder under Sample1 in the Source Control Explorer


    >Performing Manual Changes in your migrated code







    Now you are ready to perform manual changes in your branch.

  • Check out for Edit the MigratedCode folder

  • Modify code

        Private Sub Command1_Click(ByVal eventSender As Object, ByVal eventArgs As EventArgs) Handles Command1.Click
            MessageBox.Show("Command1 was clicked", Application.ProductName)
        End Sub 


        Private Sub Command1_Click(ByVal eventSender As Object, ByVal eventArgs As EventArgs) Handles Command1.Click
            //mrojas simple change for message box
            MessageBox.Show("Command1 was clicked", Application.ProductName,MessageBoxButtons.YesNo)
        End Sub 



    Check In of your changes

    Changing the VB6 Source Code

    If you have changes in your VB6 source code and you want to feed those changes to the ongoing migration, follow these steps.

    1. Check out the VB6 source code


    2. Overwrite your all sources with the new VB6 source code, or your modify the current version.

    For these example we will modify the current version, by adding a new button


    and adding some comments to our previous code. So now the VB6 code will be:

    Private Sub Command1_Click()
        'This is a sample comment for command1 code
        MsgBox "Command1 was clicked"
    End Sub
    Private Sub Command2_Click()
        'This is a sample comment for command1 code
        MsgBox "Command2 was clicked"
    End Sub
    Private Sub Command3_Click()
        MsgBox "The newly added Command3 was clicked"
    End Sub

    And after the changes we check in it back.


    Adding a new comment to identify this version



    Performing the Continuous Migration Process

    1. Check out the green code


    2. Open the VBUC and migrated again the VB6 Code. In our example the code is in C:\MergeExample\Sample1\VB6

    3. Copy the new contents of the Upgraded folder and overwrite the contents of folder GreenCode (in this case copy contents from C:\MergeExample\Sample1\VB6_UpgradedCode\Upgraded to C:\MergeExample\Sample1\GreenCode).

    4. Check in the Green Code


  • Add a descriptive comment like:
    Green Code 22-09-2009 12:34pm
    VB6 Source Code 22-09-2009 12:00pm / version 2
    VBUC version 3.0

    Now merge with current manual changes

    After migrating the modified VB6 source code and checked in it in the Source Control we now have to merge the changes between the new GreenCode and our MigratedCode.

    1. Right click on the GreenCode folder and select merge. Put attention to chech that you want to merge the “Selected ChangeSets” and that the target branch is the MigratedCode


    Click Next

    2. Select the Change sets that you will apply. The comment you use provide a guide to identify which changeset you need.


    Click Next

    3. Click Finish to perform the Merge


    4. During merge conflict might arrise. A resolve conflicts dialog will appear. Clicking the resolve conflicts button will provide different options…


    5. In our example we know that we modified the Form1.vb file so we select the “Merge changes in merge tool” option

    TIP: Typically you will just keep changes in target branch because you have already worked on those files. Specially for resource files, project files, bitmaps, etc you will leave the file in the target branch.


    6. The merge tool will appear showing the different changes and providing you a simple way to select what version to take or to manually edit the result


    7. When you are done with the Merge tool click close a dialog indicating that all conflicts have been solved will appear. Click Yes


    8. Click close in the Resolve Conflict dialog and if asked to accept the merge result click yes


    The Source Control Explorer might show marks in the modified files.


    9. Right click on the migrated code and select check in changes


    10. Type an appropiate comment indicating which versions where merged and press Check In



    And that’s all



  • Creating a new Team System Project in Visual Studio 2005

    22. September 2009 09:31 by Mrojas in General  //  Tags: , , , , , ,   //   Comments (0)


    To create a new Team System Project in Visual Studio 2005, follow these steps:

    1. Go to the File Menu. Select New…, and in the New… submenu select Team Project… to start a wizard.


    2. The “Specify the Team Project Settings” of the New Team Project wizard appears. Type the Team Project name. For example type MergeExample and click Next


    3. In the following page, select the Process Template for the Team Project. We recommend using the Artinsoft Migration Methodology – v0.8 or later. Click Next.


    4.  In the following page, type the Title for the Team Project Portal. Type MergeExample. The Team Project Portal provides useful information about your project. Click Next


    5. In the following page you select your source control settings.
    Select the first option “Create an empty source control folder”. Click Next


    6. In the following page a summary of your Team Project settings is presented. Click Finish


    7. In the following page the a process bar appears while the project is created. Just wait until the process is done. It normally takes between 3 and 5 minutes.


    Continuous Migration VBUC-MS Team System 2005: Configure MS Visual Studio 2005 to use Team System

    22. September 2009 08:57 by Mrojas in General  //  Tags: , , , , , , ,   //   Comments (0)

    This post will show you the necessary steps to configure Microsoft Visual Studio 2005 to use a Team System Project. In this example we will use a Team Project created to illustrate Continuous Migration with VBUC and MS Team System 2005, called MergeExample.

    1. Start Microsoft Visual Studio 2005

    2.  Go to the File Menu\Open\Team Project…


    3. Dialog is presented, where you can choose your Team Foundation Server, and the Team Project to use. For these Continuous Migration example we’ll assume a project called MergeExample.


    4. The Team Explorer is shown, with your selected project.
    Expand the elements for the Team Project you previously selected.


    5.  We now have to map our local directories to bind them to the
    source control system. On the expanded tree, double click on the
    Source Control Node


    6. The Source Code Explorer is shown:


    7.  Go to the Workspaces dropdown box and select Workspaces…


    8.  The Manage workspace dialog is shown.
    Select the appropiate workspace and click Edit…


    9. On the Edit Workspace dialog type a description for your source control and select the source control Folder we had created (for this example it is $/MergeExample) and the directory for your code (for this example it is C:\MergeExample).







    NOTE: if a message box about a pending update is shown, just click ok.


    Now you have successfully mapped your directories, and you can start setting up your VB6 code for continuous migration