Re: error when adding user
I read a lot of similar problems on http://dev.tikiwiki.org/ => Bug Reports List
Actually I can't load the page, so try, if you can, and have a look maybe using the different search options.
I only remember very vaguely (!), that there were mentioned perhaps to deactivate the "validate user by email", when you have checked "user can register" and "but need confirmation by admin" (all under tiki-admin.php?page=login).
Just an idea ...
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