Handle ERROR message outputs from the users point of view

[Reimar Bauer]

We have to change these messages to the view of the user. We have also to check if some are WARN.

Format should be: ERROR Fallback How can it be resolved

WARN: Problems reloading stored performance settings (<class 'UnicodeDecodeError'>: 'ascii' codec can't decode byte 0xa8 in position 21: ordinal not in range(128)). 

Switching to default!


Please update your performance settings  or remove the cached file ....

[Joern Ungermann]

This specific problem is likely the Py2/Py3 incompatibility with pickle files. If this is a warning or an error is certainly debatable.