/usr/libexec/mysqld: Incorrect key file for table ‘./DBNAME/TABLE_NAME.MYI’; Try To Repair It Error and Solution

I'm getting the following error in my mysql.log file:

100630 2:03:39 [ERROR] /usr/libexec/mysqld: Incorrect key file for table './app2_db/aix_data_user_c.MYI'; try to repair it

How do I fix this error and repair my table under UNIX or Linux operating systems?

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