>I am using C# Express 2005, which has the Masked TextBox. I tried it with a plain textbox and it worked without a problem, as you said. It looks like the new masked textbox has some formatting that somehow needs to be stripped out so that I can work with it.

I see. I updated my previous reply, did you see it? Maybe it had $ in mask and NumberStyles.Currency need to be specified.
Cetin