Gosh Glen, we seem to be going around in circles.
The code I gave you in reply #22 works... I tried it, it works with your Arduino script.
You still seem to be thrashing around trying to get the VB app to read COM 1.
The code should work if you are sending data from the Arduino to the VB on COM 1.
Even if the data doesn't match what VB is looking for, it should not give you a error message. it should just do nothing.
Are you sure that the Arduino board is sending data out on COM 1? When you open Tools/Serial Port from the menu does it say COM 1 and can you then look at the serial monitor sending out data on this port?
I guess the other question is... is your Arduino board a real Arduino board made by the folks in Italy or is it some clone made by some other company. I bought a couple of clones from China that had different chips for serial communication and I had trouble with them using the Arduino 1.0 rev and had to go back to rev .021 to even get a download.
This is probably not your problem, but I can see nothing much else to try.
Oh buy the way, it seems like way back some time you actually did get the VB to connect with the Arduino. Is that true or just my imagination?