This won't remove all users, just the "bad" ones (ones that partially exist).  You can modify it though to do what you want.  USE AT YOUR OWN RISK.

This script is property of PowerDNN, however you have permission to use and modify it as you see fit:

declare @BadIDs table (GUID uniqueidentifier)

insert into @BadIDS

Select *  From (
    Select * from (
        Select
            UserID
        from
            ASPNet_membership
    union
        Select
            UserID
        from
            aspnet_profile
    union
        Select
            UserID
        from
            aspnet_users
    ) AllPeople
   
    where
        allPeople.UserID not in (
            Select
                UserID
            from
                ASPNet_membership
            )
                OR
        allPeople.UserID not in (
            Select
                UserID
            from
                ASPNet_Profile
            )
                OR
        allPeople.UserID not in (
            Select
                UserID
            from
                ASPNet_users
            )
) as badidlist

delete from users where username in (select username from aspnet_users where userid in (select * from @BadIDs))
delete from aspnet_membership where UserID in (Select * from @BadIDs)
delete from aspnet_profile where UserID in (Select * from @BadIDs)
delete from aspnet_usersinroles where UserID in (Select * from @BadIDs)
delete from aspnet_users where UserID in (Select * from @BadIDs)

---

Tony Valenti
Tony.Valenti@PowerDNN.com
+001-402-650-6072

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