here is the code I used, you must be @ a mysql prompt, or area that accepts the mysql commands, first make sure to connect to your database, default name phpBB
ALTER TABLE ranks ADD rank_max MEDIUMINT NOT NULL;
Keep in mind ranks
may need to be changed to match your database structure.
Once i did this i had no issues with the rank system. Hope that helps someone.
Here is the Mysql docs reference: http://www.mysql.com/doc/A/L/ALTER_TABLE.html
Did you guys not read the note after the code i gave you. If you remeber when you ran install.php, there was a field labeled database prefix, if it had phpbb_ in it, they you needed to make ranks phpbb_ranks, etc.
If you were not sure, then you needed to open your phpbb database and view the table layouts and naming.....
I gave you the correct answer....you just didn't read.
If you check your ranks table and it has a rank_max field then check to make sure it is MEDIUMINT NOT NULL. in the table design from a mysql promp when you view it with will have MEDIUMINT in one description field and for the value( think it's called value), it should have a 0 (zero), not the words NULL.
If it has all that, make sure the name is right. If it is called rank_max in your database, and phpbb is looking for phpbb_rank_max, you will need to rename the field.