Hi. I don't know here is the right place for this request or not. I've downloaded Visual Studio 2010 ISO from Microsoft and got a serial number for it. I opened VB program and from the help menu (register) paste that SN into it and VB accepts that. But when I want to do that for C# I've got an error message that the SN is incorrect. Is this serial number different whit VB SN? Thank you... P.S: This is NOT a request for any serial number. I'm just talking about differences between two serial numbers. Is there any difference between VB and C# serial numbers or that was my mistake. Thank you again.