Minio on a Synology DS923+ not accessible via the web interface

I followed this step by step guide to set up the Minio on my Synology DS923+. However. I can’t access the gui using http://:9090.

I have followed the guide twice and I don’t think I have done anything differently but clearly I must have something wrong. Please could someone point me in the right direction as Googling has not solved the problem.

Is port 9090 allowed through the firewall?

Thanks for the reply.

I am trying to access the GUI interface from my LAN, so I don’t believe that I need to go through firewall

The Synology has a built-in firewall. If it’s not allowing traffic then your client cannot connect.

I turned the firewall off in the Synology but still could not connect to the Minio server via the web interface

First connect your NAS directly to PC with a LAN cable. Run the Syno Assistant. See if a static IP is stuck in there. And then check you LAN network. But if a NAS registers on a direct to PC connection. Your NAS is ok. Your LAN is blocking it.
Also if you have Win11. It has special porting permissions. This is all new for Win11 ports.