Fix

Author: SeraphJACK

src/main/java/top/seraphjack/rmc/MinecraftAdapter.java

@@ -32,6 +32,9 @@ private void logAndBroadcastMessage(String message, Object... args) {
 
     @Override
     public void preBackup() {
+        if (server.getPlayerCount() == 0) {
+            return;
+        }
         final CountDownLatch latch = new CountDownLatch(1);
         final Runnable backupAndSetNoSave = () -> {
             logAndBroadcastMessage("Backup started");