Hmm I have the same problem as a user had on the second post in this thread but it did'nt seem to be resolved heres hoping it has been now.
ERROR: Unable to insert user 10000036
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SQL: INSERT INTO phpbb_users (user_id, user_active, username, user_password, user_lastvisit, user_regdate, user_level, user_posts, user_timezone, user_style, user_lang, user_dateformat, user_viewemail, user_attachsig, user_allowhtml, user_allowbbcode, user_allowsmile, user_allowavatar, user_allow_pm, user_allow_viewonline, user_notify, user_notify_pm, user_popup_pm, user_rank, user_avatar, user_avatar_type, user_email, user_icq, user_website, user_from, user_sig, user_sig_bbcode_uid, user_aim, user_yim, user_msnm, user_occ, user_interests)
VALUES ('10000036', '1',, '',
MySQL Error: 1062 :: Duplicate entry '8388607' for key 1
if I remove a user i just get the next one and so one any ideas?