diff --git a/gns3server/crash_report.py b/gns3server/crash_report.py
index c22b0126..e38d3a9d 100644
--- a/gns3server/crash_report.py
+++ b/gns3server/crash_report.py
@@ -24,7 +24,7 @@ try:
     import raven
     RAVEN_AVAILABLE = True
 except ImportError:
-    # raven is not installed with deb package in order to simplify packagin
+    # raven is not installed with deb package in order to simplify packaging
     RAVEN_AVAILABLE = False
 
 from .version import __version__
diff --git a/gns3server/modules/iou/iou_vm.py b/gns3server/modules/iou/iou_vm.py
index e1faa345..ee8cc1ed 100644
--- a/gns3server/modules/iou/iou_vm.py
+++ b/gns3server/modules/iou/iou_vm.py
@@ -959,7 +959,7 @@ class IOUVM(BaseVM):
                     initial_config = initial_config.replace("%h", self._name)
                     f.write(initial_config)
         except OSError as e:
-            raise IOUError("Can't write initial configuration file '{}'".format(script_file))
+            raise IOUError("Can't write initial configuration file '{}': {}".format(script_file, e))
 
     @property
     def initial_config_file(self):
diff --git a/gns3server/modules/virtualbox/virtualbox_vm.py b/gns3server/modules/virtualbox/virtualbox_vm.py
index b4b2678c..f369287b 100644
--- a/gns3server/modules/virtualbox/virtualbox_vm.py
+++ b/gns3server/modules/virtualbox/virtualbox_vm.py
@@ -647,7 +647,11 @@ class VirtualBoxVM(BaseVM):
             attachment = nic_attachments[adapter_number]
             if attachment == "null":
                 # disconnect the cable if no backend is attached.
-                self._modify_vm("--cableconnected{} off".format(adapter_number + 1))
+                yield from self._modify_vm("--cableconnected{} off".format(adapter_number + 1))
+            if attachment == "none":
+                # set the backend to null to avoid a difference in the number of interfaces in the Guest.
+                yield from self._modify_vm("--nic{} null".format(adapter_number + 1))
+                yield from self._modify_vm("--cableconnected{} off".format(adapter_number + 1))
             nio = self._ethernet_adapters[adapter_number].get_nio(0)
             if nio:
                 if not self._use_any_adapter and attachment not in ("none", "null", "generic"):
@@ -683,10 +687,6 @@ class VirtualBoxVM(BaseVM):
                 if nio.capturing:
                     yield from self._modify_vm("--nictrace{} on".format(adapter_number + 1))
                     yield from self._modify_vm('--nictracefile{} "{}"'.format(adapter_number + 1, nio.pcap_output_file))
-            else:
-                yield from self._modify_vm("--nic{} null".format(adapter_number + 1))
-                yield from self._modify_vm("--cableconnected{} off".format(adapter_number + 1))
-
 
         for adapter_number in range(self._adapters, self._maximum_adapters):
             log.debug("disabling remaining adapter {}".format(adapter_number))