How to update your Minecraft server to 26.1.2: Java 25, plugins and backups

Minecraft 26.1 "Tiny Takeover" was released on 24 March 2026. The latest hotfix version is 26.1.2. It's Mojang's first release on the new year.drop.hotfix versioning system, and the first to require Java 25. That's where most servers go wrong.

This guide is for two groups: customers of our Minecraft server hosting who want to update to 26.1 through the panel, and anyone running self-hosted or with another provider. We cover what changed, what to check before updating, and the step-by-step flow for Paper, Vanilla, Forge and Fabric. Plus troubleshooting for when your server won't start after the upgrade.

Quick update steps for OXY.Games customers

The short version for our customers:

1. Create a backup first via Backups → Create backup in the panel
2. Stop your server completely
3. Go to More → Versions and select 26.1.2 (Purpur, Paper, Vanilla, Forge or Fabric)
4. Go to Startup → Java version and select Java 25
5. Start your server and check the console for errors
6. Update your plugins via More → Plugins → Installed Plugins (or mods via More → Mods)

Below, we go through each step in more detail and cover the most common problems after updating.

What is Minecraft 26.1 "Tiny Takeover"?

Released on March 24, 2026. The first game drop of 2026, and the first version using the new year.drop.hotfix naming convention. The 26 stands for the year, 1 for the first drop of that year.

The update focuses on small creatures:

• Baby mob redesign — many baby mobs got new models and animations (including Cow, Sheep, Pig, Cat, Wolf, Chicken, Rabbit, Horse and most hostile mobs). New sounds specifically for baby Wolf, Cat, Pig, Horse and Chicken
• Golden Dandelion — new flower (dandelion + 8 gold nuggets) you use to stop baby mobs from aging
• Craftable Name Tags — name tags are now craftable: 1 paper + 1 metal nugget (any type: iron, gold or copper). No longer dependent on dungeons or fishing
• Trumpet sound for note blocks on copper blocks — a note block placed on a copper block plays a trumpet sound. The tone varies by the copper's oxidation level

For server owners, the technical changes matter more than the new features.

What you need to know before updating

Four things that can break your server if you miss them.

Java 25 is required

26.1 requires Java 25. Before this, Java 21 was enough. Servers running on older Java versions won't start after the update. This is the main reason why 26.1 updates fail.

At OXY.Games, you change the Java version yourself via Startup → Java version in the panel. It doesn't switch automatically. Set it to Java 25 manually before you update to 26.1.

Self-hosted? Install Java 25 via your package manager if available, or use Adoptium Temurin 25. Then update your startup script to explicitly invoke the Java 25 binary.

Recommended RAM: 4 GB or more

Mojang adjusted the default JVM settings: the game now allocates 4 GB of RAM by default instead of 2 GB, and switches from G1GC to ZGC garbage collector on compatible systems.

For servers, this doesn't mean 4 GB is technically required — your configured server limit remains authoritative. But practically, 4 GB is a better floor for a smooth 26.1 experience, especially with multiple players, plugins or heavier worlds. Modded servers easily hit 6-8 GB.

Notice your server needs more memory after the update? At OXY.Games you can upgrade your plan without a server reinstall. The steps are in our upgrade tutorial.

Plugin and mod compatibility

Plugins for Paper, Spigot and Purpur are usually updated within days to a week after a Minecraft release. For Forge and Fabric, it takes longer.

Based on our own customer data from May 2026, Purpur is by far the most popular choice at OXY.Games, used by 38.5% of active Minecraft servers. That's no coincidence — Purpur is our default server type for new Minecraft instances and most customers stick with it. Paper (which Purpur is built on) comes second at 19.2%, followed by Forge for modded servers and Vanilla for clean, unmodified setups. For the fastest 26.1 support, we recommend Purpur or Paper — both are typically available within a week of release.

Modpacks are the risk group. Legacy modpacks often never get a 26.1 update. The developer has to update each individual mod, and for inactive packs that doesn't happen. Check your modpack's official page on CurseForge or Modrinth before getting your hopes up about an update.

World data structure has changed

Mojang reorganized the world directory structure in 26.1:

• Overworld: from the old world/ root → world/dimensions/minecraft/overworld/
• Nether: from world_nether/ (Paper) or world/DIM-1/ (Vanilla) → world/dimensions/minecraft/the_nether/
• End: from world_the_end/ (Paper) or world/DIM1/ (Vanilla) → world/dimensions/minecraft/the_end/
• Player data: now in world/players/

On the first server start after the update, Minecraft converts your world automatically. Have your own scripts or tools that read the old structure (backup scripts, world editors, map renderers)? Those need to be updated.

Back up first — no exceptions

Without a backup, a failed 26.1 update leaves you with no safe rollback path — and potentially a lost world. PaperMC explicitly warns that after upgrading to 26.1, you cannot safely downgrade to a lower version. The world data structure has changed and is one-way. So a backup is genuinely mandatory, not optional.

At our Minecraft hosting, you create a backup via the panel. Open Backups in the sidebar and click Create backup. The full tutorial with screenshots is in our docs on backups. We also run automatic daily backups in the background.

Self-hosted server? Follow this:

1. Stop the server completely
2. Copy the entire server directory to an external location. This is your backup
3. Verify that world/, world_nether/, world_the_end/, plugins/ (or mods/) and server.properties are all in the backup
4. Keep at least two backups in different locations

Step-by-step: updating your server to 26.1

The update flow is similar for every server type: stop the server, replace or update the server jar, restart, and check the console. The exact steps depend on what you run.

OXY.Games panel (the fastest route)

On an OXY.Games Minecraft server, you do the entire update in the panel:

1. Stop the server first
2. Go to More → Versions
3. Select 26.1.2 in the version dropdown (choose your server type variant: Purpur, Paper, Vanilla, Forge or Fabric)
4. Confirm the version change and wait for the installation to finish
5. Go to Startup → Java version and set it to Java 25
6. Start the server

The complete tutorial with screenshots is in our docs on server versions.

Important warning: don't switch between server types during a version update. If you go from Fabric to Paper, or Forge to Vanilla, your world, plugins and mods will not carry over automatically. Want to actually switch? Do it as a separate migration, not at the same time as the Minecraft version update.

Vanilla server (self-hosted)

1. Stop the server (stop in the console)
2. Download the 26.1 server.jar from minecraft.net
3. Replace the old server.jar
4. Check your Java version with java -version (must be 25 or higher)
5. Start with java -Xmx4G -Xms4G -jar server.jar nogui
6. Read the console output for errors

For eula.txt issues: set eula=true again if the update reset it.

Purpur / Paper server (recommended) (self-hosted)

1. Stop the server
2. Download the latest Paper 26.1 build from papermc.io
3. Replace paper-x.y.z.jar
4. Adjust your start script if it references a specific filename
5. Check your plugins/ folder and remove plugins without 26.1 support
6. Start the server, monitor [ERROR] lines in the console

Purpur (a Paper fork with extra config options) usually follows in the same week. Identical update flow.

Forge (self-hosted)

1. Stop the server
2. Download the Forge installer for 26.1.2 from files.minecraftforge.net. At time of publication, 64.0.8 was the latest build
3. Run the installer with the --installServer flag in a new directory
4. Update all mods in mods/ to 26.1 versions (1.21.x mods won't work)
5. Start the server

NeoForge (self-hosted)

NeoForge has 26.1.2 builds available as a beta release — check neoforged.net for the current version. At time of publication, 26.1.2.43-beta was the latest build for 26.1.2.

1. Stop the server
2. Download the NeoForge installer for 26.1.2
3. Run the installer in a new directory
4. Update all mods in mods/ to 26.1-NeoForge versions
5. Start the server

Running your server on a NeoForge modpack? Expect additional wait time. Even now that NeoForge itself supports 26.1, the modpack developer still has to update the pack separately. For legacy packs, that can take months, or never happen at all.

Fabric (self-hosted)

1. Stop the server
2. Download the Fabric Server Launcher for 26.1 from fabricmc.net
3. Replace fabric-server-launcher.jar
4. Update all mods in mods/ to 26.1-Fabric versions
5. Start the server

Fabric usually has faster 26.1 support than Forge. Mods are often available within 1-2 weeks.

Updating plugins and mods after the version update

Updating the server version is step one. Step two: updating your plugins or mods to 26.1-compatible versions. A 26.1 server with old 1.21.x plugins means crashes, load errors, or plugins that simply have no functionality.

Updating plugins via the OXY.Games panel

At OXY.Games you can update most plugins directly from the panel:

1. Go to More → Plugins → Installed Plugins
2. Next to each plugin with an available update, you'll see an update icon (arrow)
3. Click the icon to update that specific plugin
4. Restart the server to load the new version

Plugins without auto-update you do manually:

1. Download the 26.1-compatible version from SpigotMC, Modrinth or the official plugin page
2. Open File Manager → plugins/
3. Remove the old .jar
4. Upload the new version
5. Restart the server

Updating mods via the panel

For Forge and Fabric servers the same principle applies: More → Mods → Installed Mods gives an overview with update arrows for compatible mods.

Important exception: modpacks. Running your server on a modpack (like Better MC, Create: Astral, ATM10)? Don't update individual mods. A modpack is a specific combination of mods carefully tuned to work together. Updating mods individually breaks that balance and causes crashes. Instead, wait for an official 26.1 release of the modpack itself, and use that as the upgrade path.

Common issues after updating

Server won't start — UnsupportedClassVersionError

Symptom in console:

java.lang.UnsupportedClassVersionError: ...
has been compiled by a more recent version of Java Runtime

Or sometimes this:

Minecraft 26.1 and newer requires running the server with Java 25 or above

This means: your Java version is too low for 26.1.

Fix on self-hosted: install Java 25, and update your startup script to invoke the Java 25 binary (/usr/lib/jvm/java-25-openjdk/bin/java).

Fix on our Minecraft server hosting: open Startup → Java version in the panel, select Java 25, restart.

Plugins won't load or crash

Symptom: console shows [ERROR] Could not load plugin.

Fix:

• Check SpigotMC, Modrinth or the plugin's GitHub for a 26.1 build
• No 26.1 version? Move the plugin out of plugins/ temporarily to stabilize the server
• For major plugins (EssentialsX, LuckPerms, WorldEdit), 26.1 builds are usually available within a week of release

Mods crash — Forge or Fabric

Symptom: server crashes immediately on start, crash report points to a specific mod.

Fix:

• Remove mods one by one from mods/ to isolate the culprit
• On Modrinth you can filter by MC version 26.1 for compatible mod versions
• Running a modpack? Wait for the developer to release an official 26.1 version. Manually updating mods almost always breaks a modpack

Rolling back to your previous version

Update failed and you can't get it working?

OXY.Games customers: restore your latest backup via the Backups tab in the panel. That restores your world, plugins and configs in one go to the state before the update — no manual downgrade needed.

Self-hosted:

1. Stop the server
2. Restore your backup directory and overwrite the current world
3. Replace the jar with the previous version
4. (Forge/Fabric) Restore the previous mods/ folder
5. Start it back up

Note: players who were online after the failed update will lose their progress when you roll back.

Need help?

26.1 brings quite a few changes for server owners. Stuck somewhere?

OXY.Games customer? Contact us. Our support is available 24/7 in Dutch, English and Russian, and knows the 26.1 pitfalls from Java 25 crashes to plugin issues.

Not a customer but stuck with another host? Send us a message. We're happy to help think it through, and if you switch to OXY.Games we'll look into a personalized migration discount.

GG and happy crafting with 26.1.

Frequently asked questions

Which Java version do I need for Minecraft 26.1?

Minecraft 26.1 and later require Java 25. If you start your server with Java 21 or older, you'll usually get a startup error like UnsupportedClassVersionError. At OXY.Games you change the Java version via Startup → Java version in the panel.

Can I go back to 1.21.11 after updating to 26.1?

Not safely without a backup. PaperMC explicitly warns that after upgrading to 26.1, you can't simply downgrade — the world data structure has changed and is one-way. That's why a pre-update backup is mandatory. After a failed update, restoring a backup is the only safe rollback.

Is 4 GB RAM required for Minecraft 26.1?

No. Java 25 is required, 4 GB RAM is not. Mojang did raise the default JVM settings to 4 GB. For a normal multiplayer server, 4 GB is a better floor than 2 GB, and modded servers easily hit 6-8 GB.

Do I need to update my plugins for 26.1?

Yes. Plugins that work with items, mobs, packets, world data or server internals often break after a major Minecraft update. At OXY.Games you do this via More → Plugins → Installed Plugins by clicking the update icon next to each plugin.

Can I manually update my modpack to 26.1?

Usually not a good idea. A modpack is a specific combination of mods tuned to work together — updating individual mods breaks that balance. Wait for an official 26.1 release of the modpack. For inactive or legacy modpacks, that release may never come.

Sources

• Java Edition 26.1 official patch notes — Mojang
• Minecraft Java Edition 26.1.2 hotfix — Mojang
• Minecraft Wiki: Java Edition 26.1
• PaperMC 26.1 release notes — backup and downgrade warning
• Minecraft Forge 26.1.2 downloads — Forge builds
• NeoForge project listing — NeoForge builds
• Adoptium Temurin 25 — Java 25 builds