Reach for basic debugging tools

I have used log/trace files for years to debug real-time processes. When I started programming for Windows (1.04) the debuggers were not useable. Later, when I was debugging message handling over a serial port (hardware controled with serial interface), standard windows debuggers were of no use, hitting a break point zapped the serial data stream. Logging messages to a text file let me capture all messages and responses without stopping the serial data stream. When you need to trap code that handles the 4th copy of the same message wrong, this is the only way.