ModsFinder

RetroAuth

by Slainlight

RetroAuth fixes skin authentication for b1.7.3 on Babric and Ornithe, letting players join servers that use proper authentication and modern Minecraft skins.

BabricOrnitheClient and serverMIT LicenseOpen sourceb1.7.3

What it does

Players on b1.7.3 who connect to a server with proper authentication can otherwise run into skin problems. RetroAuth patches that path so the authentication handshake and skin loading work on Babric and Ornithe. The mod targets only b1.7.3 and is released as a single game version.

Because the fix touches both sides of the connection, it has to be installed on the server and on every client that joins it. Under the MIT License, the source code and issue tracker are public, and snapshot builds are published alongside the release files.

Key features

  1. Login handshake repair

    Repairs the authentication step so the connection to an account-verifying server completes instead of stalling.

  2. Skins from modern accounts

    Lets a b1.7.3 client display skins tied to modern Minecraft accounts when joining a server.

  3. Join flow restored

    Restores the join sequence for authenticated servers, so connections no longer fail at the login stage.

  4. Public source

    The source code and issue tracker are available, so problems can be reported and checked in the open.

No per-version build data
Modrinth lists game versions for this project (b1.7.3), but the source data has no build per game version and loader, so the compatibility grid is not shown.

Use cases

Joining authenticated servers

Players who want to play b1.7.3 on a server with proper authentication install RetroAuth on the client.

Running a legacy server

Server owners who host b1.7.3 with account verification install the mod on the server as well.

Who it’s for: The mod suits players and server owners who keep the b1.7.3 version and want authenticated servers and modern skins to work on it.

How it compares

Full comparison

LegacyAuth also covers b1.0 – b1.7.3 on Ornithe, but it is optional on either side and released under the MIT License, while RetroAuth must be installed on both sides. Parrot's Skin Changer is a client-side only Babric mod for b1.7.3 and is released under the MIT License, so servers run without it. MojangFix StationAPI Edition targets b1.7.3 on Fabric and Babric, is open source under the GNU Lesser General Public License v3.0 only, and is required on the client with the server optional.

ModLoadersGame versionsEnvironmentUpdated
RetroAuthBabric and Ornitheb1.7.3Client and server2026-07-12
LegacyAuthOrnitheb1.0 – b1.7.3Client or server, optional2025-10-15
Parrot's Skin ChangerBabricb1.7.3Client-side only2026-02-20
MojangFix StationAPI EditionFabric and Babricb1.7.3Client required, server optional2026-09-01

Questions

Does RetroAuth need to be installed on the server?

Yes. Servers that run it need every player to install it too.

Which loaders does RetroAuth support?

The mod is published for Babric and Ornithe, and only for the b1.7.3 game version.

Are snapshot builds available?

Yes, snapshot builds are published alongside the release files.

More from Slainlight

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Chisel Reborn1.17 – 26.3Cryonic Configb1.7.3 – 26.3Factory Blocks1.18 – 26.3Hot Kettles1.20 – 1.21.11Bird Nests1.20 – 1.21.7Fence On Slab!1.16 – 1.21.3

Official listing

Owner
Slainlight
Published
2025-01-12
Updated on Modrinth
2026-07-12
Facts verified
2026-10-15
Open on ModrinthCompare