Make sure that you don't have a space before or after the password (happens quickly when copy/pasting). I'll add a couple of mirrors and replace the episode with a single link soon though.
Could you please reupload these?
https://www.anime-sharing.com/threads/2003-witch-fake(フェイク)-soundtrack-op.1217706/
https://www.anime-sharing.com/threads/2000-pinpai-rebirth(リバース).1314894/
https://www.anime-sharing.com/threads/1998-pinpai-missing-itsuka-kitto-(missing-~いつかきっと~)-soundtrack-op.1210849/ https://www.anime-sharing.com/threads/2002-witch-milkyway-2-cd-soundtrack-op-ed.1431041/