Hi The RuntimeError message becomes the error "NameError: global name 'os_type' is not defined". The attached patch adds to solve this problem. Signed-off-by: Nobuhiro Itou <fj0873gn@xxxxxxxxxxxxxxxxx> Thanks, Nobuhiro Itou. diff -r 73d38353c139 virtinst/FullVirtGuest.py --- a/virtinst/FullVirtGuest.py Fri Mar 16 14:32:06 2007 -0400 +++ b/virtinst/FullVirtGuest.py Mon Mar 19 18:26:07 2007 +0900 @@ -72,7 +72,7 @@ class FullVirtGuest(Guest.XenGuest): if FullVirtGuest.OS_TYPES[self._os_type].has_key(val): self._os_variant = val else: - raise RuntimeError, "OS variant %s does not exist in our dictionary for OS type %s" % (val, os_type) + raise RuntimeError, "OS variant %s does not exist in our dictionary for OS type %s" % (val, self._os_type) os_variant = property(get_os_variant, set_os_variant) def set_os_type_parameters(self, os_type, os_variant):