diff --git a/test/file/test-fs-ownergroup.js b/test/file/test-fs-ownergroup.js
index 113ea74c..d23915cf 100644
--- test/file/test-fs-ownergroup.js
+++ test/file/test-fs-ownergroup.js
@@ -38,7 +38,7 @@ exports.testChangeOwner = function() {
     assert.equal(fs.owner(testFile), java.lang.System.getProperty("user.name"));
 
     assert.throws(function() {
-        fs.changeOwner(testFile, "thisuserdoesnotexistforsureonthissystem" + Date.now());
+        fs.changeOwner(testFile, "doesnotexist" + Date.now());
     }, java.nio.file.attribute.UserPrincipalNotFoundException);
     assert.equal(fs.owner(testFile), java.lang.System.getProperty("user.name"));
 };
@@ -52,7 +52,7 @@ exports.testChangeGroup = function() {
     var oldGroup = fs.group(testFile);
 
     assert.throws(function() {
-        fs.changeGroup(testFile, "thisgroupdoesnotexistforsureonthissystem" + Date.now());
+        fs.changeGroup(testFile, "doesnotexist" + Date.now());
     }, java.nio.file.attribute.UserPrincipalNotFoundException);
 
     assert.isTrue(fs.changeGroup(testFile, oldGroup));