diff --git a/LaunchServer/src/main/java/ru/gravit/launchserver/socket/websocket/json/auth/AuthResponse.java b/LaunchServer/src/main/java/ru/gravit/launchserver/socket/websocket/json/auth/AuthResponse.java
index 76ea0089..f3d771ae 100644
--- a/LaunchServer/src/main/java/ru/gravit/launchserver/socket/websocket/json/auth/AuthResponse.java
+++ b/LaunchServer/src/main/java/ru/gravit/launchserver/socket/websocket/json/auth/AuthResponse.java
@@ -45,6 +45,11 @@ public void execute(WebSocketService service, ChannelHandlerContext ctx, Client
                 AuthProvider.authError(LaunchServer.server.config.authRejectString);
                 return;
             }
+            if(!clientData.checkSign)
+            {
+                AuthProvider.authError("Don't skip Launcher Update");
+                return;
+            }
             AuthProvider provider = LaunchServer.server.config.authProvider[authid];
             AuthProviderResult result = provider.auth(login, password, ip);
             if (!VerifyHelper.isValidUsername(result.username)) {