[Error Message] MyBB has experienced an internal SQL error

[what4]

Can anyone help me with this problem? when logging in to my forum I get this error
MyBB has experienced an internal SQL error and cannot continue.

SQL Error:
145 - Table './#######_bb123/mybb_userfields' is marked as crashed and should be repaired
Query:
SELECT u.*, f.* FROM mybb_users u LEFT JOIN mybb_userfields f ON (f.ufid=u.uid) WHERE u.uid='1' LIMIT 1

[faviouz]

Run this query in phpMyAdmin:

REPAIR TABLE `mybb_userfields`

[what4]

Thank you.