I have been having the same "password required" issues since the last update. Today I went to FileHippo and downloaded previous version 1.14..451 and started a scan. It turns out that the older version found an additional 2.4 GB of crap to delete--crap that the latest version has not been deleting. I'm guessing that the issue with the new version may be more than just a password request; I'm afraid that the latest version may not be adequately doing the job.