I have been problems with the USB CDC task, if I use priority 0 or 1 it does create the task but it never runs. If I use 2 or 3, it creates the task, enumerates and it works… What could be the problem?

So you have a task at priority 1 that is starving all lower priority tasks or taking up too much CPU for the USB protocol timing?

Actually, it would be a priority 2 task (unless his timer interrupt isn’t working), as a priority 1 task would round robin with another priority task. If possible, try stopping the program with a debugger and see what task is running. My guess is it is a priority 2 task that doesn’t wait for something that isn’t available, therefore starving the lower priority tasks.

You are right dave. Still don’t know how to fix it, but at least I know why now… Thanks,
Renan