When I try to use the nvis module in Grass, QGis, pops-up a warning window saying "Module nviz not found". how can I solve this issue and use the nviz?
I faced a very similar problem a while ago: Unable to load 'nviz' through GRASS
For me, downloading/installing WinGRASS-6.4.1 and running GRASS 6.4.1.exe seperately from QGIS worked. I was able to use nviz (after configuring the project location and mapsets etc).
I still can't run it through QGIS for some reason but seems to work perfectly if I run it on its own.