Hi @hkozubek . Are the server and tv on the home network?
You may have to give the server a reserved ip address in the router and configure plex on tv with new ip address.
If that doesn't work, can you give more detail on the setup?
@hkozubek . The Mac should show you its tcp/ip details. It will be 192.168.1.something. Default gateway will be 188.8.131.52.1.1 (the router). Put this ip address in the address bar of browser and login to router.
What model router do you have?
Look at network status screen for a client list. Your Mac will be there with other connected devices. The server should get a fixed ip address in case the router is rebooted.
@hkozubek . It seems like a Synology DS218+.
Press the Reset button once to reset network settings.
But only do it once!
Check in router to see if server shows up.
Userid is admin and password blank.
1. Press and hold until you hear a beep sound to restore the default IP address, DNS server, and passwords for the admin account.
(Don't do the following.)
2. Press and hold until you hear a beep sound, then press and hold again until you hear three beep sounds to return the DiskStation to “Not installed” status so that DiskStation Manager (DSM) can be reinstalled