If running install or update RVsitebuilder return the following error.

Connection rvglobalsoft.com port 80 :                                          [ Failed ]
Connection 404 Not Found

Just run full RVsitebuilder 6 installation with the following command.

cd /usr/src; rm -fv rvsitebuilderinstall.sh; wget http://download.rvglobalsoft.com/rvsitebuilderinstall.sh; chmod +x rvsitebuilderinstall.sh; ./rvsitebuilderinstall.sh

Then login to WHM as root. Go to WHM > Plugins > and run RVglobalsoft manager then follow simple install process.