Seems I'm having this exact issue with W10 build 19044.1826 and it's not limited to explorer.exe: this is a fresh install of W10 too. The fuq? EDIT: solved, there are 2 user accounts and other one was still logged in. Logging out of the other removed duplicate entries. I hadn't remembered to disable the setting for "finalize updates using these credentials..." from user account settings for the other account.