Bedrock Error Code Door or Terracotta: How to Fix Server Joins

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What Mojang says the Bedrock error codes Door, Terracotta and Block mean, and the NetherNet fixes for BDS, home servers, Geyser, Aternos and Realms.

A pile of Minecraft blocks: grass, bricks, planks, sandstone and diamond ore

Your Bedrock players pick your server and get "Multiplayer Connection Failed" with error code Door, Terracotta, Block or NetherNet. Since Bedrock 26.60 (27 October 2026) and Mojang's switch from RakNet to NetherNet on 29 October, a server that is not ready for NetherNet turns players away with these codes. Below: Mojang's own meaning for each code, then the official and the community fixes for a Bedrock Dedicated Server (BDS), a home server behind CGNAT, Geyser, Aternos and Realms.

Quick answer: Mojang's error list says Door means "There was a multiplayer connection error", Terracotta "An unspecified error has occurred" and Block "There was an issue with the Minecraft data being sent or received", and publishes nothing more specific. For your own BDS, Mojang's fix is to update to 26.60 or newer, set transport=nethernet and open port 19132 for TCP and UDP. If outside players still get Door, owners on Mojang's bug tracker fixed it by putting their public IPv4 address in server-udp-ports, a community fix. Behind CGNAT, use a NetherNet tunnel or a hosted server instead of port forwarding. "You're not invited to play on this server" points to the allow-list, on by default since 26.30.

What Mojang says each error code means

Mojang's help center list Named Error Code Troubleshooting for Minecraft: Bedrock Edition, last edited on 15 September 2026, has these entries for the codes server players report now:

CodeMojang's meaningMojang's next step
Door"There was a multiplayer connection error."Network connection troubleshooting
NetherNet"There was a multiplayer connection error."Network troubleshooting, then the unable-to-join guide
Terracotta"An unspecified error has occurred."General error code troubleshooting
Block"There was an issue with the Minecraft data being sent or received."Remove Character Creator items, custom skins and add-ons
Boat"An error occurred."General error code troubleshooting
Chain"The server or player you're trying to connect with has a different version of Minecraft."Update the game
Arrow"There was an error connecting to a Realm."Realms connection troubleshooting

Mojang says nothing more about them. Terracotta is not specific to NetherNet either: a 2021 report on Mojang's bug tracker, MCPE-142234, is titled "Failed to Login Error Code "Terracotta"". For such codes, Mojang's general troubleshooting is to sign out and restart, update, disable add-ons and check the PlayFab and Xbox status pages.

Press Show details on the error screen too: it shows an InitialConnection number, such as InitialConnection-83, and the transport in use. Aternos and GeyserMC both ask for that screen.

Why the codes show up now

Mojang made NetherNet "the default transport used by dedicated servers" in 26.50 (15 September 2026), and the 26.60 changelog of 27 October turned the server's NetherNet warning into "an error when users are not using NetherNet, as RakNet is deprecated". Mojang's Bedrock server setup article, edited on 28 October, adds: "On Thursday, October 29, 2026, we are rolling out a Networking change, migrating from RakNet to NetherNet." Mojang warns that some players running self-hosted servers "may see an "Unsupported Transport" Error 149", and logs posted on Mojang's tracker show BDS printing a TRANSPORT TYPE ERROR at startup: "Your current connection type is not set to NetherNet."

A NetherNet join has two stages. The guide that ships with BDS says the server listens on TCP on server-port "for an HTTP-based signaling handshake, then negotiates a UDP connection with each client that carries the gameplay traffic." In the reports we read on Mojang's tracker and GitHub, Door appeared when the first stage worked and the second did not.

Fix a Bedrock Dedicated Server: Mojang's steps

Mojang's notice about the 29 October change lists three steps:

  1. Update BDS to 26.60 or newer. It does not update itself, and on 31 October 2026 Mojang's download page linked 1.26.61.1. An outdated server can also cause Chain.
  2. Open port 19132 for TCP and UDP, in the router and the host firewall.
  3. Set transport=nethernet in server.properties. Stop the server before you edit the file, then start it.

Mojang's update steps copy your old configuration into the new installation, so old defaults survive. We compared server.properties in Mojang's own downloads:

Your server.properties hasShipped inChange it to
transport=raknet1.26.30.5 to 1.26.44.3transport=nethernet
# server-udp-ports= (commented out)1.26.30.5 to 1.26.52.3server-udp-ports=19132
No transport line1.26.23.1 and oldertransport=nethernet (the default, now explicit)

The second row matters because without server-udp-ports, "UDP ports are allocated from the operating system's ephemeral port range", so your UDP 19132 forward misses. Mojang's setup article calls that default "suitable for most LAN and outbound-friendly home networks", but the 26.60 download ships these lines, which match the TCP and UDP 19132 advice:

server-port=19132
server-udp-ports=19132
transport=nethernet

Also run serveridentity save in the console once after the first start. Without a saved key, the BDS guide says, the server gets a new identity at every start, "causing players to have to re-accept server trust". Back up the keys folder it creates.

Test the server from outside

Mojang's NetherNet onboarding guide documents the client's first request, GET /v1/join, which a NetherNet server answers with JSON holding its name, version and player count. Run it from another connection, such as a phone hotspot, since "some routers cannot connect back to their own public address from inside the home network" (Mojang):

curl -i http://203.0.113.10:19132/v1/join
  • JSON with your server name: TCP signaling works, so Door points at UDP (next section).
  • A timeout or "Connection refused": TCP does not reach BDS. Check the forward, the firewall and server-port; our port forwarding guide covers the router side.

Door behind a home router: publish your public IP

If /v1/join answers but players still get Door, BDS may be offering an address they cannot reach. Mojang's onboarding guide warns that a host behind NAT has local addresses "that remote clients cannot reach", and the BDS guide documents a public IP prefix for server-udp-ports, as IP:public:local:

server-udp-ports=203.0.113.10:19132:19132

As a fix for Door, this is a community finding. Mojang's tracker ticket BDS-23108 ("Transport type "nethernet" renders server inaccessible") is open, and Mojang's triage team reviewed it on 19 October without posting a fix. In it, an owner behind NAT on 1.26.51.1 changed only this line, and an outside player who had failed with Door connected and spawned. Other findings:

  • An IP, not a hostname. In itzg Docker image issue #673, a DNS name in this field gave Door although /v1/join returned 200; the IP worked. Update the line if your home IP changes.
  • LAN players may lose access. The same BDS-23108 tester's Xbox at home could not join with the mapping in place.
  • Start with one port. Before 26.60, owners reported that the range form did not publish the public address while one server-udp-ports= line per port did, and one found that their router silently ignored a range forward. The 26.60 file describes a single UDP port "shared by all clients".
  • Docker: publish TCP 19132 next to the UDP ports.

One reporter wrote on 29 October that 26.60 did not fix the Boat error on their LAN, so check the ticket before you count on the update.

Home server behind CGNAT: use a NetherNet tunnel

Mojang says port forwarding "may not work if your connection uses carrier-grade NAT, double NAT, or a network that you do not control", and points to Realms or a hosting provider. A tunnel that supports NetherNet is the third way. Playit.gg rewrote its guides for it (our playit.gg guide has the general setup):

  • Tunnel type: "Minecraft Bedrock (NetherNet), not Minecraft Bedrock", marked experimental, with playit 1.1.0 or newer. Its pricing page lists it under Free on 31 October 2026.
  • BDS: "Bedrock Dedicated Server can't connect to playit by itself," says playit's BDS guide, so WaterdogPE, a free proxy, runs next to it. BDS moves to port 19142, and players join the tunnel address on port 19132.
  • Door through playit: check the tunnel type and "Make sure WaterdogPE is running and players are using port 19132."
  • Geyser: playit's Geyser guide uses the same tunnel type.

A tunnel still needs your PC on whenever people play. Mojang's other suggestion is a hosting provider: every Space-Node Minecraft plan runs Bedrock directly or Java with Geyser, with three port allocations included.

Geyser servers

Bedrock players on a Java server join through Geyser, which had to make the same switch: Geyser 2.12.1 build 1273 or newer (build 1279 was the newest on 30 October), transport: nethernet in its config, and the Geyser port open for TCP and UDP. GeyserMC's support bot ties InitialConnection-83 on the details screen to a server "running behind a NAT setup" and the advertise-addresses option. Our Geyser NetherNet guide covers the config, the ports, Warden and the trust prompt.

Aternos

Aternos updated its NetherNet article on 30 October 2026: Bedrock players now connect on port 19132 for every Aternos server, Geyser included, and "Anyone who added your server to their list before the change will have to edit it to change the port." Its checklist: port 19132, a current server or Geyser version, a current BedrockTogether if you use it, signing out of your Microsoft account and back in, the allowlist disabled in the options, no Bedrock add-ons, and another internet connection.

Realms

A Realm runs on Mojang's servers, and Mojang's NetherNet notice is about self-hosted ones. Mojang's list calls Arrow "an error connecting to a Realm", and its Realms troubleshooting is to sign out and restart, update, check the console and Realms subscriptions, and have the owner close and reopen the Realm: Realms Hub, Settings, Server, Temporarily Close Realm, then Open Realm. Non-members see "Realm not found, or you are not a member." Since 26.60, owners can invite players "without the extra step of making them an Xbox friend."

"You're not invited to play on this server"

This is the game's own text (disconnectionScreen.notAllowed in Mojang's 1.26.60.5 language file), and on a new BDS the allow-list is behind it. Mojang's 26.30 changelog of 16 June 2026: "Dedicated servers now have the allow list enabled by default in the server.properties, and will display a warning on server startup if the allow list is enabled but contains no entries". The 1.26.23.1 download shipped allow-list=false; 1.26.30.5 and later ship allow-list=true with an empty allowlist.json, and Mojang's setup article says every player must be added, "including operators". Microsoft Learn's server.properties page, last updated on 25 June 2025, still lists false.

Add players in the server console:

allowlist add YourGamertag
allowlist add "Gamertag With Spaces"
allowlist list

Per the BDS guide, the Gamertag is enough because the account ID is resolved "the first time the player connects", hand edits to allowlist.json need allowlist reload, and allowlist on or allowlist off changes only the running server, not server.properties.

Do not switch online-mode off instead. Mojang says to keep it on for any server reachable from the internet, the game refuses the mix ("Using an allowlist without online authentication can be dangerous and is not allowed."), and since 26.60 "Dedicated servers now exit cleanly when incompatible allow-list and online-mode settings are configured." The exception is a proxy that signs players in itself, like playit's WaterdogPE setup: it runs BDS with online-mode=false and allow-list=false, since WaterdogPE "still checks that every player is signed in to Xbox."

FAQ

How do I fix the Bedrock NetherNet "Door" error? Run BDS 26.60 or newer with transport=nethernet, server-udp-ports=19132 and port 19132 open for TCP and UDP. If Door remains while /v1/join answers from outside, add your public IPv4 address to server-udp-ports, the community fix above. Behind CGNAT, use a NetherNet tunnel; on Aternos, port 19132.

Why do Bedrock players get the Terracotta error on my Aternos server? Mojang only calls it "an unspecified error", so work through Aternos's checklist. On a Java server, also check that it starts at all: Geyser runs as a plugin inside it, so while Paper or Spigot is down, nothing accepts Bedrock players.

Can I switch my server back to RakNet? No. A user on the CubeCoders forum still got past Door on 6 October by forcing RakNet, but that ended with 26.60 and the 29 October rollout. Aternos: "Using the old RakNet protocol is no longer possible in this version."

Why did the 26.60 update break crossplay through BedrockTogether? Relay apps like BedrockTogether sit between the console and the server and need their own NetherNet support; Aternos says to keep it updated. For Block, Mojang's steps are to remove Character Creator items, switch to a default skin and disable add-ons. Our console guide lists other routes from Xbox, PlayStation and Switch.

Why can friends on my Wi-Fi join, but not friends outside? Outside players need TCP and UDP to reach the server, and an address they can reach, so check both forwards and the public IP mapping above. If your router's WAN address lies between 100.64.0.0 and 100.127.255.255, the block RFC 6598 set aside for carrier-grade NAT, port forwarding cannot make the server reachable: use a tunnel or a host.

Why does my new server say "You're not invited to play on this server"? Since 26.30 the allow-list is on by default and starts empty, so nobody gets in, operators included. Run allowlist add YourGamertag in the server console for each player.

Sources

All opened on 31 October 2026: