I have a VB6 program that uses MSComm control to send/receive data via COM port. I occasionally get this runtime error 8012 "The device is not open".
I have found reference to this error but I can not find any reference to exactly what would cause this error. I would like to know the possible reasons that cause this error to occur?
[EDIT]: I don't have access to its source code.
The program tried to use the COM port and it wasn't open for use. This is a bug in the program where it tries to use the port without checking if it opened it successfully.