diff --git a/test/ruby/test_file_exhaustive.rb b/test/ruby/test_file_exhaustive.rb
index d3a44d1234..8a33258759 100644
--- a/test/ruby/test_file_exhaustive.rb
+++ b/test/ruby/test_file_exhaustive.rb
@@ -514,7 +514,7 @@ class TestFileExhaustive < Test::Unit::TestCase
     assert_equal File.join(new_home, "bar", "foo"), File.expand_path("foo", "~/bar"), bug8034
 
     assert_raise(ArgumentError) { File.expand_path(".", UnknownUserHome) }
-    assert_nothing_raised(ArgumentError) { File.expand_path("/", UnknownUserHome) }
+    assert_nothing_raised(ArgumentError) { File.expand_path("#{DRIVE}/", UnknownUserHome) }
   ensure
     ENV["HOME"] = home
   end