UBB.threads PHP Forum Software Community Forums UBB.threads 7 Version 7 Support Resetting User Count {v. 7.2.2.}

You could delete users excluding the admin and reset the auto increment field, however all of the posts are not going to be visible, since they are tied to the actual userid, so without it, they just won't display.

You could delete the users through the control panel and that would tie all of the posts to the guest user, but not too sure if that's what you want?