DB error when delete user

[ales2cv]

When in administration choise user and go deletit first get confirm then after delete get that error.

Database error in vBulletin 4.1.4:

Invalid SQL:

DELETE FROM vb_blog_usercss
WHERE userid = 5590;

MySQL Error : Incorrect key file for table 'vb_blog_usercss'; try to repair it
Error Number : 1034
Request Date : Friday, July 15th 2011 @ 03:28:23 AM
Error Date : Friday, July 15th 2011 @ 03:28:23 AM
Script : http://www.cxxcom/forum/admincp/user.php?do=kill
Referrer : http://www.cxx.com/forum/admincp/use...=remove&u=5590
IP Address : 88.200.92.236
Username : 2cv
Classname : vB_Database
MySQL Version : 5.1.56


How could i fix that