diff --git a/launcher/server.py b/launcher/server.py
index c9d22e8..114c365 100644
--- a/launcher/server.py
+++ b/launcher/server.py
@@ -381,6 +381,19 @@ def start_gmweb():
         _logf("gmweb：%d 已在监听，跳过启动" % GM_WEB_PORT)
         return
 
+    if getattr(sys, "frozen", False):
+        # A frozen onefile launcher must not spawn itself for gmweb: the
+        # child keeps the parent _MEI directory open after the window closes,
+        # which makes PyInstaller report "Failed to remove temporary directory".
+        _logf("gmweb: frozen mode uses in-process server")
+        start_gmweb_inproc(script)
+        for _ in range(30):
+            if port_open(GM_WEB_PORT):
+                _logf("gmweb: http://127.0.0.1:%d/ ready" % GM_WEB_PORT)
+                return
+            time.sleep(0.2)
+        return
+
     try:
         kwargs = {"cwd": os.path.dirname(script),
                   "stdout": subprocess.DEVNULL,