Problem with HTTP connection between Win client machine and Linux server with successfully installed MS8.0

Hello,

I just successfully installed MS8.0 on my linux machine (server/gateway) including the licensing !

Unfortunately when I tried to register/acces this gateway from my Windows client machine I have obtained
"Error in http test". On the other hand the ping test was OK.

When I tried to put  http://server_name_OR_IP:18888  into my web browser on client Win machine
I obtained error:

---------------------------------
This webpage is not available

ERR_CONNECTION_TIMED_OUT
------------------------------


On the other hand when I run "gwtest" on that linux server (in MaterialsStudio8.0/etc/Gateway) it finished as the success:

[mara@dyn-138-252 Gateway]\$ ./gwtest
Testing gateway installation for script u/dsd_test.pl
Running GET for url http://server_name_OR_IP:18888/dsd/commands/u/dsd_test.pl

It works! ...

This is the simple cgi test output ...
Test succeeded, it appears!

When I tried (again on that linux server)

curl  http://server_name_OR_IP:18888/dsd/commands/u/dsd_test.pl

it again works perfectly and print:

-----------------------------------------------------------------------


403 Forbidden

Forbidden


You don't have permission to access /dsd/commands/u/dsd_test.pl
on this server.




Apache/2.2.29 (Unix) mod_perl/2.0.4 Perl/v5.8.9 Server at machine_name Port 80


------------------------------------------------------------

So on the side of the Linux server gateway is running, everything works perfectly including http communication (but here just locally).

HTTP communication from another machine (e.g. my client Windows machine) to the Linux server with MS8.0 installation does not work.

I would appreciate any useful advice regarding this problem e.g. what to try check/test/set to get working HTTP connection
between Win client and Linux server. Thank you in advance. Marek