MSComm Serial Error 8021 "Internal error retrieving device control block for the port"

Question

Occasionally we get this error when communicating between my motion control software and a plasma cutting torch. What the serial link is being used for is a one time setup of cutting information before the cutting begins. I am using VB6 and MSComm for this.

I know the port itself has lunched because after it occurs other serial comm software (diagnostics, etc) can't access the port either. I would like to understand what MSCOmm is doing when it received this error so I can find a better hardware solution.

Answer 1

Mscomm32.ocx is still fully supported by Microsoft. You could ask their support people to help. If you have an MSDN subscription, you may be entitled to free support incidents.

Apologies if you'd already thought of that, I hope someone else can give you a direct solution.

Answer 2

Try using a different OCX

www.comm32.com has a control that mimics mscomm but has many improvements