Changing text of textbox in C#

[mhmani21]

Hi.
I have a problem with setting the text of a textbox from a Class Library.
Basically I recieve couple of string from the server, then have to pass the information the main form and set those strings as text of couple of textboxes and lables.
I did this by opening a new form and setting texts it was fine. But for some reasons I'm not supposed to open a new form. So I defined a function in main form, it's void, and it reads a file and sets strings in the textboxes. The problem is that it won't show the text! I debug the project, put break point, move the mouse on textBox1 and it said the text is whatever it reads from the file, but i dont see it in the textbox.
The only thing that I think may be causing the problem is that all these textboxes are in a groupbox. However if i set a text in main_Load there is no problem. I tried sending the info straight to the fnction, and skipped the file thing, but didnt work either.
I tried using function in another project without groupbox and there is no probelm.
Does anyone know how I can overcome this problem? It's urgent.
thanks

[Logan1337]

If the property is being properly set (as you imply by verifying this using breakpoints) then it sounds like a refresh issue. Try explicitly calling TextBox.Refresh ().