LP2 - Message about pen being in error state

Question
Every now and then we get error messages in penDirector log when docking a pen: Pen is in error state.
What does it mean?

Answer
The pen goes into an 'error state' when it doesn't respond to command within 2 seconds. We mark such a pen as in an 'error state' since we cannot get any information from it.
Usually re-docking the pen, performing a factory reset or docking it in a different USB port helps to resolve this problem.