Can not connect to a Minecraft world

Hello there.

Your friend's server is Dedicated, or hosted by himself (launched in game)?

Wich NAT Type he have?

If he's playing on the Bedrock addition (they mention Xbox and Windows 10 edition) then I would say it's a realm.

Do you have multiple consoles at your house? and what realm subscription is it?

Hello there.

Your friend's server is Dedicated, or hosted by himself (launched in game)?

Wich NAT Type he have?

Have you tried the Minecraft help/support forums? They may also be able to help or have answers to this issue. Here is a link, best of luck and I hope you're able to connect again soon!

https://help.minecraft.net/hc/en-us

If the console is stuck updating, try to turn off the console, and hold the Bind button (the small button next to the USB ports on newer Xbox 360 consoles, or the small button next to the Memory Unit slots on older 360 consoles), and keep that button held
down when you power up the console.

As for your Minecraft world:

If you are still able to somehow boot the console, and copy the savegame over to an USB drive, you can go to a working Xbox 360 that can connect online, and load your world there.

Then, with an updated Xbox 360 Minecraft, move your world to the cloud.

Now comes the hard part: Find someone with a "Minecraft Xbox One Edition" (not the newer Xbox One "Minecraft" without the "Xbox One Edition").

You can then download your world into that "Minecraft Xbox One Edition", and then this world can be imported into "Minecraft".

Similar issue here, except trying to connect AppleTV minecraft to Windows App version. Connecting AppleTV to world hosted on Windows results in Disconnected message. Hosting world on AppleTV, I can see the world listed, but when connecting to it, I just
go back to the worlds list.

AppleTV is running 1.1.5 - latest version I assume

Windows has 1.2.8.

Is it the mismatch in versions causing the issue?