grass - QGIS 3.4 error: utf-8' codec can't decode byte 0xe8 in position 50: invalid continuation byte

I have the following error message every time I try to run a GRASS algorithm in QGIS 3.4. I unistalled the software and installed it again but I did not solve anything.

Traceback (most recent call last):
File "C:/PROGRA~1/QGIS3~1.4/apps/qgis/./python/plugins\processing\algs\grass7\Grass7Algorithm.py", line 415, in processAlgorithm
Grass7Utils.executeGrass(self.commands, feedback, self.outputCommands)

File "C:/PROGRA~1/QGIS3~1.4/apps/qgis/./python/plugins\processing\algs\grass7\Grass7Utils.py", line 372, in executeGrass
for line in iter(proc.stdout.readline, ''):
File "C:\PROGRA~1\QGIS3~1.4\apps\Python37\lib\codecs.py", line 322, in decode
(result, consumed) = self._buffer_decode(data, self.errors, final)
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xe8 in position 50: invalid continuation byte