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What "Mod resolution failed" means on Fabric
"Mod resolution failed" means Fabric could not find a set of your mods that fits together, so it refused to start the game. Every Fabric mod states what it needs: a Minecraft version, a Fabric Loader version, often Fabric API, sometimes a Java version and other mods. Fabric puts all of those wishes side by side before anything loads. When one of them cannot be met, you get this.
Console, Fabric server
[main/WARN]: Mod resolution failed
[main/INFO]: Immediate reason: [HARD_DEP_NO_CANDIDATE xaerominimap 26.6.1 {depends fabric-api @ [>=0.43.1]}, ...]
[main/INFO]: Fix: add [add:fabric-api 0.43.1 ([[0.43.1,∞)])], remove [], replace []
[main/ERROR]: Incompatible mods found!
net.fabricmc.loader.impl.FormattedException: Some of your mods are incompatible with the game or each other!
A potential solution has been determined, this may resolve your problem:
- Install fabric-api, version 0.43.1 or later.
More details:
- Mod 'Xaero's Minimap' (xaerominimap) 26.6.1 requires version 0.43.1 or later of fabric-api, which is missing!Skip the lines with Immediate reason, Reason and Fix: they are the same information in Fabric's internal shorthand. The two blocks to read are the potential solution, which says what to do, and More details, which says which mod asked for it. Everything after that is a stack trace and can be ignored.
A potential solution has been determined: what each line asks you to do
| The solution line | What it means | What to do |
|---|---|---|
Install fabric-api, version 0.43.1 or later. | A mod needs Fabric API and it is not on the server | Add Fabric API for your Minecraft version |
Install simplybows, version 0.1.4. | An add-on needs the mod it belongs to | Add that mod, in exactly the version named |
Replace mod 'Fabric Loader' (fabricloader) 0.18.4 with version 0.19.3 or later. | A mod is newer than your Fabric Loader | Update Fabric Loader; your mods can stay |
Replace 'Minecraft' (minecraft) 26.2 with any 26.3.x version. | The mods were made for another Minecraft version | Use mod files for your version, or change the server's version |
Replace 'OpenJDK 64-Bit Server VM' (java) 25 with version 21. | A mod insists on a specific Java version | Run the Minecraft version that mod was built for |
Remove mod ... | A mod clashes with the rest and nothing else fixes it | Take that jar out of mods |
The names in these lines are mod IDs, the short names Fabric uses inside the game. In the More details block each one also appears with its title in quotes, as in Mod 'Xaero's Minimap' (xaerominimap), which makes it easy to find on a download page. Search for the title, not the ID.
Fabric suggests, it does not guarantee
The heading says the solution may resolve your problem, and it means it. Fabric only knows about the mods that are on the server. After you follow the suggestion, the next start can turn up a new requirement from the mod you just added. Two or three rounds is normal on a big mod list.
requires fabric-api, which is missing: install Fabric API
requires ... of fabric-api, which is missing! is the most common Fabric start error, and the simplest. Fabric API is a separate mod that most Fabric mods build on, and it is not part of Fabric Loader. A fresh Fabric server does not have it until you add it, and many mod lists forget it because players' launchers install it quietly.
On the Mods tab, search the verified catalog for Fabric API and choose Verify & install; the catalog only offers releases for your server's Minecraft version. If you upload it yourself, take the file for exactly your Minecraft version: a Fabric API built for 26.3 on a 26.2 server gives the next error in this guide, requires any 26.3.x version of 'Minecraft'.
but only the wrong version is present: Minecraft, Fabric Loader or Java
"But only the wrong version is present" means the thing a mod needs is on the server, in a version the mod does not accept. The name before it tells you which part is off. Three of them are not mods at all: minecraft, fabricloader and java.
requires any 26.3.x version of 'Minecraft'
The mod was made for another Minecraft version than the server runs. On Fabric this is strict: a mod for 1.20.1 does not run on 26.3, and a dozen mods from an old pack will each say so. Either download each mod again in the release for your server's version, or set the server to the version the mods were made for in Settings, card Server software. Mind your world when you go back to an older version; a world saved by a newer one will not load, as explained in failed to load datapacks.
requires version 0.16.10 or later of mod 'Fabric Loader'
Fabric Loader itself is older than the mod wants. The loader is installed with the server software, not dropped in the mods folder, so downloading it as a mod does nothing. Ask our team to update the Fabric Loader on your server; your mods and world stay exactly where they are. Older loaders are a common sight on servers that were set up a while ago, because mods move on faster than the loader on an existing server.
requires version 21 of 'OpenJDK 64-Bit Server VM' (java)
A few mods name an exact Java version instead of a minimum, and refuse to load on a newer one. On our panel the Java runtime follows the Minecraft version: choosing a version in Settings installs the server software again with the Java that belongs to it, Java 21 for 1.21.1 and Java 25 for 26.1 and newer. If the console shows a Java that does not match your version, pick the version again there. The Java version guide has the full table.
can't be loaded due to other constraints, disabled for this environment, and incompatible
These three lines look scarier than they are. Each points back to a problem that appears elsewhere in the same list, or to a mod that does not belong on a server.
| Text in More details | What it means |
|---|---|
which can't be loaded due to other constraints! | The mod it needs is there, but cannot load itself because of another line in the list. Fix that line first; this one usually disappears with it. |
which is disabled for this environment (client/server only)! | A mod depends on something that only runs in the game on a player's computer. The mod asking for it is usually a client mod too; remove it from the server. |
is incompatible with ... | The author of a mod marked another mod as breaking it. Keep one of the two, or look for releases that work together. |
The line SERVER environment disabled: [...] near the top is not an error. It lists the parts of Fabric API and of your mods that only run on players' computers, such as the screen and keybind modules, which Fabric switches off on a server on purpose. Client-only mods that do get loaded crash a server in a different way, explained in client-only mods on a server.
How to fix Incompatible mods found on your Fabric server
Copy the solution block
From the console or
logs/latest.log, copy everything fromA potential solution has been determineddown to the stack trace. That is your list of work.Handle the version lines first
If the list asks to replace
minecraft,fabricloaderorjava, decide that first. Swapping the Minecraft version changes which mod files you need, so there is no point in downloading mods before that is settled.Add and replace the mods
Install every mod the solution names, in the version it names, for your Minecraft version. The Mods tab's verified catalog brings required dependencies along; files you upload yourself go into
modson the Files tab with the server stopped.Start and read the next list
Start the server. A shorter list means progress; repeat until the console reaches
Done. Keep the jars your players need in their own mod list too.
Written and checked by the Lodehost team, last reviewed on 7 November 2026.
