diff --git a/tests/vagrant/funcs.rb b/tests/vagrant/funcs.rb
index b4f485cf..b304e242 100644
--- a/tests/vagrant/funcs.rb
+++ b/tests/vagrant/funcs.rb
@@ -8,6 +8,7 @@
 #####
 
 def use_preloaded_box(obj, name, preloaded_dir=".")
+  obj.vm.box = String.new(name)
   _name=name.sub! '/','-'  # ubuntu/bionic64 => ubuntu-bionic64
   if File.file?("#{preloaded_dir}/preloaded/preloaded-#{_name}.box")
     # box name needs to be unique on the system
@@ -17,8 +18,6 @@ def use_preloaded_box(obj, name, preloaded_dir=".")
       # do not update additions when booting this machine
       obj.vbguest.auto_update = false
     end
-  else
-    obj.vm.box = name
   end
 end