diff --git a/gns3server/modules/base_manager.py b/gns3server/modules/base_manager.py
index aef1579a..8788e5f1 100644
--- a/gns3server/modules/base_manager.py
+++ b/gns3server/modules/base_manager.py
@@ -99,9 +99,10 @@ class BaseManager:
 
         for uuid in self._vms.keys():
             try:
-                self.delete_vm(uuid)
+                yield from self.delete_vm(uuid)
             except Exception as e:
                 log.warn("Could not delete VM {}: {}".format(uuid, e))
+                continue
 
         if hasattr(BaseManager, "_instance"):
             BaseManager._instance = None
diff --git a/gns3server/server.py b/gns3server/server.py
index 1fdeb876..f0c885a9 100644
--- a/gns3server/server.py
+++ b/gns3server/server.py
@@ -80,7 +80,7 @@ class Server:
         for module in MODULES:
             log.debug("Unloading module {}".format(module.__name__))
             m = module.instance()
-            m.unload()
+            self._loop.run_until_complete(m.unload())
         self._loop.stop()
 
     def _signal_handling(self):