No problem was detected proceeding with an upgrade of the NoMachine installation to the version 7.1.3 from a previous 7 install.

Problem occurs only when a previous NoMachine v. 7 is uninstalled and then NoMachine v. 7.1.3 is installed. After that, user is no longer able to connect to the physical desktop.

Error is: a new display cannot be established

This problem affects all kind of Linux installations (RPM, DEB and TAR.GZ) of NoMachine free and Enterprise Desktop. There is an error in the uninstall procedure that leaves leftovers in the /usr/NX directory and this prevents a further installation.

As a workaround:
upgrade NoMachine v. 7 to v. 7.1.3 without uninstalling the current version before.

To fix the problem when it occurs, instead:
- uninstall v. 7.1.3
- remove the /usr/NX and /var/NX directories
- install again NoMachine v. 7.1.3