There are a number of serial classes available. I have one in my book (see
below) with examples, and there are several online. Also, there is a serial
control for .NET in the Visual Basic Resource Kit, which is available free
of charge from Microsoft.
If you want a "drop-in" replacement for MSComm, you can download NETComm.ocx
from my homepage. It too is free.
Author of Visual Basic Programmer's Guide to Serial Communications, 4th
Edition ISBN 1-890422-28-2 (391 pages) published July 2004. See www.mabry.com/vbpgser4 to order.