diff --git a/gns3server/handlers/api/controller/project_handler.py b/gns3server/handlers/api/controller/project_handler.py
index f9f12ba7..03930494 100644
--- a/gns3server/handlers/api/controller/project_handler.py
+++ b/gns3server/handlers/api/controller/project_handler.py
@@ -456,8 +456,9 @@ class ProjectHandler:
                     if not packet:
                         break
                     f.write(packet)
-
         except FileNotFoundError:
             raise aiohttp.web.HTTPNotFound()
         except PermissionError:
             raise aiohttp.web.HTTPForbidden()
+        except OSError as e:
+            raise aiohttp.web.HTTPConflict(text=str(e))