UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 1484: ordinal not in range(128)

Handling http error 404 raises exception 
UnicodeDecodeError: 'ascii' codec can't decode byte 0xe2 in position 1484: ordinal not in range(128)

Related issue https://github.com/liftoff/GateOne/issues/249