diff --git a/gns3server/modules/virtualbox/__init__.py b/gns3server/modules/virtualbox/__init__.py
index 24f2f684..8e7754fb 100644
--- a/gns3server/modules/virtualbox/__init__.py
+++ b/gns3server/modules/virtualbox/__init__.py
@@ -115,6 +115,45 @@ class VirtualBox(BaseManager):
 
             return stdout_data.decode("utf-8", errors="ignore").splitlines()
 
+    @asyncio.coroutine
+    def _find_inaccessible_hdd_files(self):
+        """
+        Finds inaccessible disk files (to clean up the VirtualBox media manager)
+        """
+
+        hdds = []
+        properties = yield from self.execute("list", ["hdds"])
+        flag_inaccessible = False
+        for prop in properties:
+            try:
+                name, value = prop.split(':', 1)
+            except ValueError:
+                continue
+            if name.strip() == "State" and value.strip() == "inaccessible":
+                flag_inaccessible = True
+            if flag_inaccessible and name.strip() == "Location":
+                hdds.append(value.strip())
+                flag_inaccessible = False
+        return reversed(hdds)
+
+    @asyncio.coroutine
+    def project_closed(self, project):
+        """
+        Called when a project is closed.
+
+        :param project: Project instance
+        """
+
+        yield from super().project_closed(project)
+        hdd_files_to_close = yield from self._find_inaccessible_hdd_files()
+        for hdd_file in hdd_files_to_close:
+            log.info("Closing VirtualBox VM disk file {}".format(os.path.basename(hdd_file)))
+            try:
+                yield from self.execute("closemedium", ["disk", hdd_file])
+            except VirtualBoxError as e:
+                log.warning("Could not close VirtualBox VM disk file {}: {error}".format(os.path.basename(hdd_file), e))
+                continue
+
     @asyncio.coroutine
     def get_list(self):
         """
diff --git a/gns3server/modules/virtualbox/virtualbox_vm.py b/gns3server/modules/virtualbox/virtualbox_vm.py
index e0a181be..ed1580ab 100644
--- a/gns3server/modules/virtualbox/virtualbox_vm.py
+++ b/gns3server/modules/virtualbox/virtualbox_vm.py
@@ -321,7 +321,6 @@ class VirtualBoxVM(BaseVM):
 
         if self._linked_clone:
             hdd_table = []
-            hdd_files_to_close = []
             if os.path.exists(self.working_dir):
                 hdd_files = yield from self._get_all_hdd_files()
                 vm_info = yield from self._get_vm_info()
@@ -332,7 +331,6 @@ class VirtualBoxVM(BaseVM):
                         port = match.group(2)
                         device = match.group(3)
                         if value in hdd_files:
-                            hdd_files_to_close.append(value)
                             log.info("VirtualBox VM '{name}' [{id}] detaching HDD {controller} {port} {device}".format(name=self.name,
                                                                                                                        id=self.id,
                                                                                                                        controller=controller,
@@ -353,12 +351,6 @@ class VirtualBoxVM(BaseVM):
             log.info("VirtualBox VM '{name}' [{id}] unregistering".format(name=self.name, id=self.id))
             yield from self.manager.execute("unregistervm", [self._name])
 
-            for hdd_file in hdd_files_to_close:
-                log.info("VirtualBox VM '{name}' [{id}] closing disk {disk}".format(name=self.name,
-                                                                                    id=self.id,
-                                                                                    disk=os.path.basename(hdd_file)))
-                yield from self.manager.execute("closemedium", ["disk", hdd_file])
-
             if hdd_table:
                 try:
                     hdd_info_file = os.path.join(self.working_dir, self._vmname, "hdd_info.json")