[Qgis-user] Help with ERROR: Incomplete GRASS session: Variable 'LOCATION_NAME' not set

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Hello,

I've been trying to use GRASS Tools in QGIS 3.40.15 Bratislava but when I
run the tools I get the error messages: ERROR: MAPSET is not set,
and, ERROR: Incomplete GRASS session: Variable 'LOCATION_NAME' not set, and
then it says "The following layers were not created correctly".

When I try to run GRASS GIS 8.4.2 on its own I get the same error and the
program doesn't start. I am attaching two screenshots, one from inside QGIS
and the other from trying to start GRASS GIS on its own. I've been looking
around but can't seem to find any solution but I think it might have
something to do with the fact that the "Location for GRASS docs" space is
empty inside the processing options in QGIS.

I've tried reinstalling QGIS both through the express and advanced options
in the osgeo4w-setup installer but the problem is still there.

I am using Windows 11 OS-version 26100.7623.

Thanks in advance!
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