diff --git a/src/main/java/moe/yushi/authlibinjector/AuthlibInjector.java b/src/main/java/moe/yushi/authlibinjector/AuthlibInjector.java
index 785c0d9..b3fe885 100644
--- a/src/main/java/moe/yushi/authlibinjector/AuthlibInjector.java
+++ b/src/main/java/moe/yushi/authlibinjector/AuthlibInjector.java
@@ -51,6 +51,7 @@ import moe.yushi.authlibinjector.transform.DumpClassListener;
 import moe.yushi.authlibinjector.transform.SkinWhitelistTransformUnit;
 import moe.yushi.authlibinjector.transform.YggdrasilKeyTransformUnit;
 import moe.yushi.authlibinjector.transform.support.CitizensTransformer;
+import moe.yushi.authlibinjector.transform.support.LaunchWrapperTransformer;
 import moe.yushi.authlibinjector.util.Logging;
 import moe.yushi.authlibinjector.yggdrasil.CustomYggdrasilAPIProvider;
 import moe.yushi.authlibinjector.yggdrasil.MojangYggdrasilAPIProvider;
@@ -332,6 +333,7 @@ public final class AuthlibInjector {
 
 		transformer.units.add(new ConstantURLTransformUnit(urlProcessor));
 		transformer.units.add(new CitizensTransformer());
+		transformer.units.add(new LaunchWrapperTransformer());
 
 		transformer.units.add(new SkinWhitelistTransformUnit(config.getSkinDomains().toArray(new String[0])));
 
diff --git a/src/main/java/moe/yushi/authlibinjector/transform/support/LaunchWrapperTransformer.java b/src/main/java/moe/yushi/authlibinjector/transform/support/LaunchWrapperTransformer.java
new file mode 100644
index 0000000..49de2aa
--- /dev/null
+++ b/src/main/java/moe/yushi/authlibinjector/transform/support/LaunchWrapperTransformer.java
@@ -0,0 +1,50 @@
+package moe.yushi.authlibinjector.transform.support;
+
+import static org.objectweb.asm.Opcodes.ALOAD;
+import static org.objectweb.asm.Opcodes.ASM7;
+import static org.objectweb.asm.Opcodes.INVOKEVIRTUAL;
+import static org.objectweb.asm.Opcodes.RETURN;
+
+import java.util.Optional;
+
+import org.objectweb.asm.ClassVisitor;
+import org.objectweb.asm.MethodVisitor;
+
+import moe.yushi.authlibinjector.transform.TransformUnit;
+
+public class LaunchWrapperTransformer implements TransformUnit {
+
+	@Override
+	public Optional<ClassVisitor> transform(ClassLoader classLoader, String className, ClassVisitor writer, Runnable modifiedCallback) {
+		if ("net.minecraft.launchwrapper.LaunchClassLoader".equals(className)) {
+			return Optional.of(new ClassVisitor(ASM7, writer) {
+				@Override
+				public MethodVisitor visitMethod(int access, String name, String descriptor, String signature, String[] exceptions) {
+					if ("<init>".equals(name)) {
+						return new MethodVisitor(ASM7, super.visitMethod(access, name, descriptor, signature, exceptions)) {
+							@Override
+							public void visitInsn(int opcode) {
+								if (opcode == RETURN) {
+									modifiedCallback.run();
+									super.visitVarInsn(ALOAD, 0);
+									super.visitLdcInsn("moe.yushi.authlibinjector.");
+									super.visitMethodInsn(INVOKEVIRTUAL, "net/minecraft/launchwrapper/LaunchClassLoader", "addClassLoaderExclusion", "(Ljava/lang/String;)V", false);
+								}
+								super.visitInsn(opcode);
+							}
+						};
+					} else {
+						return super.visitMethod(access, name, descriptor, signature, exceptions);
+					}
+				}
+			});
+		} else {
+			return Optional.empty();
+		}
+	}
+
+	@Override
+	public String toString() {
+		return "LaunchWrapper Support";
+	}
+}