Hello.
First lets rule out the easy stuff.
There could be two issues here:
1. When on “no sessions available” screen, please make sure the view is set to “All desktops”.
2. Please make sure the user you are connecting with is marked as an administrator for NoMachine.
On licenses other than Enterprise Desktop we have something called “restricted access” to physical desktop, and the user has to be specifically marked as administrator to have full access to Login Window and desktop sessions.
If the user account has already been used to access NoMachine, please use:
/etc/NX/nxserver --useredit username --administrator yes
if not, please use:
/etc/NX/nxserver --useradd username --administrator yes
And try to connect again.
If this does not help please gather logs for investigation.
As it is Catalina, please gather information from the MacOS system log, preferably by running:
# cat /var/log/system.log | grep -e nxserver -e nxnode -e nomachine >> system.debug
and
/usr/bin/log show --debug | grep -e nxserver -e nxnode -e nomachine >> log.debug
Also please collect NoMachine logs.
Article on how to collect logs:
https://www.nomachine.com/DT10O00163 (“How to gather debug logs for support requests”)
Please include the system.debug file and send them to forum[at]nomachine[dot]com using the title of
that forum’s thread as the mail’s subject.
/Mth