COM problems with MS Word

I wanted to build a VB.NET class file which would replace words in a Word Document. Now, the unique thing about it is I guess it is COM, meaning I have to strong name it.

After many problems with trying to strong name the reference to Word.Interop, I found this documentation:

I followed the VB.NET instructions to the tee, and it worked. I thought it was clear sailing from there...apparently not. The new reference I added was MyWord.dll which was the result of the documentation. I then declared it with the following:

Dim ThisApplication As MyWord.Application // to replace the regular Word.Application instance

Ok still going good...VS.NET recognizes all objects, methods, and properties of the regular MS Word Libs with MyWord.dll

Next, I take the project, put it onto a different computer, and register all the typelibs via regasm and then the assembly with gacutil.

Working good for like:

Dim my_text As String

Public Property mytext()
Return my_text
End Get
Set(ByVal Value)
my_text = Value
End Set
End Property

But as soon as I call this function via COM from my other application:

Public Sub SearchReplace()
End Sub

Everything stops with this error:

File or assembly name MyWord, or one of its dependencies, was not found.

Now I know that the Documents.Open() method exists, because my VS.NET sees it in object viewer. Could it be that I'm developing on 1 computer and then trying to make it work with another computer (I've registered and gac'ed on both computers).

Thanks in advance.
Who is Participating?
I had some trouble too,.. Are you sure all needed .dll are on the pther (non developing) system?

I used this commando's to register my assemblies:

gacutil /if myfile.dll
regasm myfile.dll

But in order to have these tools function fully I needed on the 'other' machine (.Net Framework v1.1 installed) the following files:

msvcr71.dll  <<

Maybe it solves your problem... It is tricky to get this working, there are linkers on the market; they solve all these dependencies by adding all these used .net references ( ..etc) to your assembly: ( is an example)

Hopes it helps you a bit... Daniël

BTW: there are many ppl asking questions about strong naming. It is quite easy with the free tool Deadbolt.Net. You can find it here:

> After install you create your own token (key) via tools>>create... (vs.net2003).
> To digitally sign (strong name) your project, right-click on the Assembly.vb file in your project and choose "Digitally sign"

This tools saves you lot of time in the future signing your things

forgot: try resigning your assembly (with the tool) never know....
drakkarnoirAuthor Commented:
I figured it required me to register MyWord.dll via gacutil...

gacutil /i MyWord.dll

Now that message is gone, but I have another error:

Object reference not set to an instance of an object.

This happens when I reference any object or method.
Hello,..  I am happy the problem was solved easy...

The other thins "...Object reference not set to an instance of an object.."

Mostly this occurs when you do this:

   'Define it
   Dim i as Formtest

   'Use it (within a button_click or something...)

In some cases (classes..) you need to define (like this one)

dim i as Formtest = new formtest  'So the New() function inside gets called

If you define a var as string (Dim a as string) you don't use it...

So try this NEW thing... Else the object is still "Nothing" and then you get this error.

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