Re: Login only by reset email
No idea, just a guess. Ensure that you are not using an old theme style not updated to 3.x.
Change the theme style to thenews or strasa.
In case your old theme was using a non-updated tiki-login_scr.tpl (or similar), this would (should) enforce you to use the standard one.
If no luck with this tip, no idea myself.
HTH
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