unfortunately as Sasha says, you need to get your members to try to use the forgot password function and see if that resolves the problem. because there is no porting script available from any other software, this work can be tedious and time consuming.
you can try this as well
there was hack on here that removed the SALT feature, maybe trying to look that up will help, but i would say using SALT is a decent security measure.
you can go try to login to each of your members accounts and fire the forgot password function yourself, and that will email your members a new password.
i will look at getting a sql statement written that will look at the SALT column and if '' then change the password and randomize so salt will be generated.
at any rate. not much help i know, just thought i would chime in.
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