Upgrading to 5.1.26 Incorrect key file

[Wolfgang Purrer]

My Problem ist after the update from 5.0.51a to 5.1.26rc (both windows 2003) i got with some tables (6 out of 100) the message:

Error : Incorrect key file for table 'xx'; try to repair it
error : Corrupt

On the old system i checked the table .. and everything was ok. I also tried to repair the table (on the old system) .. everthing ok. (the table has only 2 columns and 8 rows) ... in there wasn't a change of the data for this table in the last years. I also did a nice shotdown on the table.

If i try to repair the table on the new systems i got the the message (incorrect key file...)

the create Statement for the table is:

CREATE TABLE `ifdes`.`zuordnung_messdaten` (
`messwertenummer` tinyint(3) unsigned NOT NULL default '0',
`Messwertbezeichnung` char(30) default '0',
PRIMARY KEY (`messwertenummer`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1;