Sudden Database error? HELP please

[MyndJack21]

Just wondering if anybody can help me with this.
We have been running SMF for nearly a year now without any problem.

Suddenly, today, after making no changes we get this error message:

*************************
Database Error
Incorrect key file for table './myndjack_forums/smf_log_online.MYI'; try to repair it
File: /home1/myndjack/public_html/forums/Sources/Subs.php
Line: 2540

Note: It appears that your database may require an upgrade. Your forum's files are currently at version SMF 1.1.6, while your database is at version 1.1.5. The above error might possibly go away if you execute the latest version of upgrade.php. 

******************************

One second I posted and it was working fine, then 2 minutes later we get this error.
Can anybody  help me with what to do to fix this?
Thanks

Oh and the site adress is:

hxxp:www.myndjack.com/forums/index.php [nonactive]

[karlbenson]

try repairing the smf_log_online table in your database in PHPMYADMIN.

[MyndJack21]

yeah that did the trick...thanks