Content originally posted in LPCWare by DiligentMinds.com on Thu Aug 30 10:55:08 MST 2012
Windows has this issue with *ANY* USB serial device. You *MUST* use the "safely remove device" action in Windows, or you are going to see this. This happens even with off-the-shelf USB-to-Serial cables. If you have a program up (like TeraTerm Pro for example) that is using the serial port, and you reach over and just unplug the cable, you *may* have to restart Windows to recover from the evil that ensues...
BTW-- Linux does not do this, and handles this situation just fine. Since Apple's OS/X is based on OpenBSD, I'm guessing that *IT* won't have any issues either. In Linux, any program in the process of using the serial port (that you just unplugged) might have to be restarted, but that is the extent of the evil. I don't own an Apple machine, so I can't test that. Maybe someone else here can test this and let us know?
So, (in summary), you need to properly inform Windows that you would like to remove the USB CDC device (after closing any programs that are using it)-- and wait for Windows to give you permission to unplug the device. This is *NOT* the fault of NXP-- the fault lands squarely on the shoulders of Microsoft. This is inherent in the goofy architectural "design" of Windows, and there is nothing anyone (but Microsoft) can do about it.