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.
Try using a different OCX
http://www.comm32.com has a control that mimics mscomm but has many improvements