diff --git a/src/fmllauncher/java/net/minecraftforge/fml/loading/moddiscovery/InvalidModIdentifier.java b/src/fmllauncher/java/net/minecraftforge/fml/loading/moddiscovery/InvalidModIdentifier.java
index bbd97fd2f..e3e931594 100644
--- a/src/fmllauncher/java/net/minecraftforge/fml/loading/moddiscovery/InvalidModIdentifier.java
+++ b/src/fmllauncher/java/net/minecraftforge/fml/loading/moddiscovery/InvalidModIdentifier.java
@@ -36,6 +36,7 @@ public enum InvalidModIdentifier {
     FABRIC(filePresent("fabric.mod.json")),
     LITELOADER(filePresent("litemod.json")),
     OPTIFINE(filePresent("optifine/Installer.class")),
+    BUKKIT(filePresent("plugin.yml")),
     INVALIDZIP((f,zf) -> !zf.isPresent());
 
     private BiPredicate<Path, Optional<ZipFile>> ident;
diff --git a/src/main/resources/assets/forge/lang/en_us.json b/src/main/resources/assets/forge/lang/en_us.json
index 9258369c1..ad6034288 100644
--- a/src/main/resources/assets/forge/lang/en_us.json
+++ b/src/main/resources/assets/forge/lang/en_us.json
@@ -56,6 +56,7 @@
   "fml.modloading.brokenfile.liteloader": "File {2} is a LiteLoader mod and cannot be loaded",
   "fml.modloading.brokenfile.fabric": "File {2} is a Fabric mod and cannot be loaded",
   "fml.modloading.brokenfile.optifine": "File {2} is an incompatible version of OptiFine",
+  "fml.modloading.brokenfile.bukkit": "File {2} is a Bukkit or Bukkit-implementor (Spigot, Paper, etc.) plugin and cannot be loaded",
   "fml.modloading.brokenfile.invalidzip": "File {2} is not a jar file",
   "fml.modloading.brokenresources": "File {2} failed to load a valid ResourcePackInfo",
   "fml.modloading.missinglicense": "Missing License Information in file {3}",