diff --git a/gns3server/controller/export_project.py b/gns3server/controller/export_project.py
index 0c282f1b..29226fc7 100644
--- a/gns3server/controller/export_project.py
+++ b/gns3server/controller/export_project.py
@@ -16,6 +16,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 import os
+import sys
 import json
 import asyncio
 import aiofiles
diff --git a/gns3server/controller/project.py b/gns3server/controller/project.py
index 00829912..c1da4586 100644
--- a/gns3server/controller/project.py
+++ b/gns3server/controller/project.py
@@ -1083,7 +1083,7 @@ class Project:
         assert self._status != "closed"
 
         try:
-            proj = await self._fast_duplication(name, location, reset_mac_addresses)
+            proj = await self._fast_duplication(name, reset_mac_addresses)
             if proj:
                 if previous_status == "closed":
                     await self.close()
@@ -1091,7 +1091,7 @@ class Project:
             else:
                 log.info("Fast duplication failed, fallback to normal duplication")
         except Exception as e:
-            raise aiohttp.web.HTTPConflict(text="Cannot duplicate project: {}".format(str(e)))
+            raise ControllerError(f"Cannot duplicate project: {str(e)}")
 
         try:
             begin = time.time()
@@ -1332,7 +1332,7 @@ class Project:
     def __repr__(self):
         return f"<gns3server.controller.Project {self._name} {self._id}>"
 
-    async def _fast_duplication(self, name=None, location=None, reset_mac_addresses=True):
+    async def _fast_duplication(self, name=None, reset_mac_addresses=True):
         """
         Fast duplication of a project.
 
@@ -1349,7 +1349,7 @@ class Project:
                 log.warning("Fast duplication is not supported with remote compute: '{}'".format(compute.id))
                 return None
         # work dir
-        p_work = pathlib.Path(location or self.path).parent.absolute()
+        p_work = pathlib.Path(self.path).parent.absolute()
         t0 = time.time()
         new_project_id = str(uuid.uuid4())
         new_project_path = p_work.joinpath(new_project_id)
diff --git a/tests/compute/docker/test_docker_vm.py b/tests/compute/docker/test_docker_vm.py
index debae032..c48c301d 100644
--- a/tests/compute/docker/test_docker_vm.py
+++ b/tests/compute/docker/test_docker_vm.py
@@ -1812,10 +1812,10 @@ async def test_cpus(compute_project, manager):
                         ],
                         "Privileged": True,
                         "Memory": 0,
-                        "NanoCpus": 500000000
+                        "NanoCpus": 500000000,
+                        "UsernsMode": "host"
                     },
                 "Volumes": {},
-                "UsernsMode": "host",
                 "NetworkDisabled": True,
                 "Hostname": "test",
                 "Image": "ubuntu:latest",
@@ -1863,10 +1863,10 @@ async def test_memory(compute_project, manager):
                         ],
                         "Privileged": True,
                         "Memory": 33554432,  # 32MB in bytes
-                        "NanoCpus": 0
+                        "NanoCpus": 0,
+                        "UsernsMode": "host",
                     },
                 "Volumes": {},
-                "UsernsMode": "host",
                 "NetworkDisabled": True,
                 "Hostname": "test",
                 "Image": "ubuntu:latest",