MyBB Community Forums

I recently merged my old phpbb3 board to mybb. All of the old usergroups were converted and more than 8000 members now reside in a usergroup called REGISTERED. All new members however are in the default mybb user-group Registered. Can I merge the two groups together? Or if I delete the old merged REGISTERED user-group will the members be moved to the default one?

update mybb_users set usergroup=x where usergroup=y;

Substitute your GOOD GID for x and your OLD GID for y.

Do you mean run a sql query?
update mybb_users set usergroup=Registered where usergroup=REGISTERED;