I created a new test application per your suggestion and it worked perfectly.  I then went back into my original project, removed all Infragistics references, and then added them back in again, and I no longer get the error.

It appears something with my project/solution file was not quite right, but re-adding the references did the trick.

Thanks again for the quick and helpful replies.  I appreciate it!

-Randy

I doubt the language would have any effect, although I did use C# to test it out before, worked fine for me.  Nor do I think the trial version would have anything in it to short it out, the other dlls worked fine according to you, so singling out MaskedEdit would seem a little odd.

 I had one of our Developer Support Engineers try out the issue in VB.Net and he was able to get the class to subclass. So it does not seem language specific.

I guess what you could try would be to start a test windows form application, drag a masked edit control onto the form which will load the references.  Ensure that all three are there, if any are missing I would guess that the installer didn't put them into the GAC (not likely but possible).  After that delete the MaskedEdit from the form and add a class file to the winforms solution that you subclass the masked edit with and see if that works.

If that fails, then you would have a project to submit to developer support so that they could debug it. 

Thanks for the quick reply! I appreciate it.

 I do have references to both of those .dlls and the same error persists.  I should also mention that I'm using a trial version (that does not expire for another 10 days of usage).  Would this have any impact?

Otherwise, would the fact that I'm using Visual Basic be a problem?  I have not yet attempted this with C# yet, but I can give it a go if that would help diagnose this.

 -Randy

You should also have a reference to the Infragistics2.Win.dll and Infragistics2.Shared.dll.