3
The Rank is completely unimportant. Its just optical.
You need to verify that your users still have the groupmembership in the admin group.
The groupid for webmasters is "1" as you can see if you browse the table (your_db_prefix)_groups.
Now in the (your_db_prefix)_users table lookup which uid your previous admins have.
(most likely your first user with uid 1 is an admin)
With the knowledge of the userid of one of your admins you can finally look into the table _groups_users_link.
The table linking your users to a group is (your_db_prefix)_groups_users_link. So if you browse that one you should see an entry like
linkid [size=x-small](any number)[/size] groupid [size=x-small]1[/size] uid [size=x-small]1[/size] (or the uid of the user you are looking for)
e.g. [size=x-small]6 1 1[/size] would mean that the sixth entry in the list(unimportant) defines group 1 (webmasters) to include user 1 (first created user of your site)
If that doesnt help as hervet said please provide an error message. Also you could turn on debugging with an admin user. Search the faq on how to do that.
Sorry, this signature is experiencing technical difficulties. We will return you to the sheduled signature as soon as possible ...