diff --git a/gns3server/modules/base_manager.py b/gns3server/modules/base_manager.py
index 056ad8fc..ad12a784 100644
--- a/gns3server/modules/base_manager.py
+++ b/gns3server/modules/base_manager.py
@@ -237,7 +237,7 @@ class BaseManager:
     @asyncio.coroutine
     def close_vm(self, vm_id):
         """
-        Delete a VM
+        Close a VM
 
         :param vm_id: VM identifier
 
@@ -305,7 +305,8 @@ class BaseManager:
 
         vm = yield from self.close_vm(vm_id)
         vm.project.mark_vm_for_destruction(vm)
-        del self._vms[vm.id]
+        if vm.id in self._vms:
+            del self._vms[vm.id]
         return vm
 
     @staticmethod
diff --git a/gns3server/modules/dynamips/__init__.py b/gns3server/modules/dynamips/__init__.py
index bc888b23..d2cc958e 100644
--- a/gns3server/modules/dynamips/__init__.py
+++ b/gns3server/modules/dynamips/__init__.py
@@ -357,7 +357,10 @@ class Dynamips(BaseManager):
         ghost_ios_support = self.config.get_section_config("Dynamips").getboolean("ghost_ios_support", True)
         if ghost_ios_support:
             with (yield from Dynamips._ghost_ios_lock):
-                yield from self._set_ghost_ios(vm)
+                try:
+                    yield from self._set_ghost_ios(vm)
+                except GeneratorExit:
+                    log.warning("Could not create ghost IOS image {} (GeneratorExit)".format(vm.name))
 
     @asyncio.coroutine
     def create_nio(self, node, nio_settings):
diff --git a/gns3server/modules/virtualbox/virtualbox_vm.py b/gns3server/modules/virtualbox/virtualbox_vm.py
index 08a567fd..350bd92e 100644
--- a/gns3server/modules/virtualbox/virtualbox_vm.py
+++ b/gns3server/modules/virtualbox/virtualbox_vm.py
@@ -279,7 +279,7 @@ class VirtualBoxVM(BaseVM):
         try:
             with open(hdd_info_file, "r", encoding="utf-8") as f:
                 hdd_table = json.load(f)
-        except OSError as e:
+        except (ValueError, OSError) as e:
             raise VirtualBoxError("Could not read HDD info file: {}".format(e))
 
         for hdd_info in hdd_table: