diff --git a/dlls/advapi32/tests/security.c b/dlls/advapi32/tests/security.c
index a1a44bb..222bfb0 100644
--- a/dlls/advapi32/tests/security.c
+++ b/dlls/advapi32/tests/security.c
@@ -2254,10 +2254,9 @@ static void test_ConvertStringSecurityDescriptor(void)
     SetLastError(0xdeadbeef);
     ret = pConvertStringSecurityDescriptorToSecurityDescriptorA(
         "D:(D;;GA;;;Nonexistent account)", SDDL_REVISION_1, &pSD, NULL);
-    todo_wine
-    ok(!ret && GetLastError() == ERROR_INVALID_ACL,
-        "ConvertStringSecurityDescriptorToSecurityDescriptor should have failed with ERROR_INVALID_ACL instead of %d\n",
-        GetLastError());
+    ok(!ret, "Expected failure, got %d\n", ret);
+    ok(GetLastError() == ERROR_INVALID_ACL || GetLastError() == ERROR_INVALID_SID,
+       "Expected ERROR_INVALID_ACL or ERROR_INVALID_SID, got %d\n", GetLastError());
 }
 
 static void test_ConvertSecurityDescriptorToString()
@@ -2353,16 +2352,22 @@ static void test_ConvertSecurityDescriptorToString()
     ok(pConvertSecurityDescriptorToStringSecurityDescriptorA(&desc, SDDL_REVISION_1, sec_info, &string, &len), "Conversion failed\n");
     CHECK_RESULT_AND_FREE("O:SYG:S-1-5-21-93476-23408-4576D:S:");
 
+    /* fails in win2k */
     SetSecurityDescriptorDacl(&desc, TRUE, NULL, FALSE);
     pAddAuditAccessAceEx(pacl, ACL_REVISION, VALID_INHERIT_FLAGS, KEY_READ|KEY_WRITE, psid2, TRUE, TRUE);
-    ok(pConvertSecurityDescriptorToStringSecurityDescriptorA(&desc, SDDL_REVISION_1, sec_info, &string, &len), "Conversion failed\n");
-    CHECK_ONE_OF_AND_FREE("O:SYG:S-1-5-21-93476-23408-4576D:S:(AU;OICINPIOIDSAFA;CCDCLCSWRPRC;;;SU)", /* XP */
-        "O:SYG:S-1-5-21-93476-23408-4576D:NO_ACCESS_CONTROLS:(AU;OICINPIOIDSAFA;CCDCLCSWRPRC;;;SU)" /* Vista */);
+    if (pConvertSecurityDescriptorToStringSecurityDescriptorA(&desc, SDDL_REVISION_1, sec_info, &string, &len))
+    {
+        CHECK_ONE_OF_AND_FREE("O:SYG:S-1-5-21-93476-23408-4576D:S:(AU;OICINPIOIDSAFA;CCDCLCSWRPRC;;;SU)", /* XP */
+            "O:SYG:S-1-5-21-93476-23408-4576D:NO_ACCESS_CONTROLS:(AU;OICINPIOIDSAFA;CCDCLCSWRPRC;;;SU)" /* Vista */);
+    }
 
+    /* fails in win2k */
     pAddAuditAccessAceEx(pacl, ACL_REVISION, NO_PROPAGATE_INHERIT_ACE, FILE_GENERIC_READ|FILE_GENERIC_WRITE, psid2, TRUE, FALSE);
-    ok(pConvertSecurityDescriptorToStringSecurityDescriptorA(&desc, SDDL_REVISION_1, sec_info, &string, &len), "Conversion failed\n");
-    CHECK_ONE_OF_AND_FREE("O:SYG:S-1-5-21-93476-23408-4576D:S:(AU;OICINPIOIDSAFA;CCDCLCSWRPRC;;;SU)(AU;NPSA;0x12019f;;;SU)", /* XP */
-                          "O:SYG:S-1-5-21-93476-23408-4576D:NO_ACCESS_CONTROLS:(AU;OICINPIOIDSAFA;CCDCLCSWRPRC;;;SU)(AU;NPSA;0x12019f;;;SU)" /* Vista */);
+    if (pConvertSecurityDescriptorToStringSecurityDescriptorA(&desc, SDDL_REVISION_1, sec_info, &string, &len))
+    {
+        CHECK_ONE_OF_AND_FREE("O:SYG:S-1-5-21-93476-23408-4576D:S:(AU;OICINPIOIDSAFA;CCDCLCSWRPRC;;;SU)(AU;NPSA;0x12019f;;;SU)", /* XP */
+            "O:SYG:S-1-5-21-93476-23408-4576D:NO_ACCESS_CONTROLS:(AU;OICINPIOIDSAFA;CCDCLCSWRPRC;;;SU)(AU;NPSA;0x12019f;;;SU)" /* Vista */);
+    }
 }
 
 static void test_PrivateObjectSecurity(void)
-- 
1.5.4.3