All of a sudden my users are getting the following error for an item that does exist:

126
Incorrect key file for table './blabber9_joom1/#__k2_items.MYI'; try to repair it SQL=UPDATE #__k2_items SET `hits` = (`hits` + 1) WHERE `id` = '75124'
It appears the page you were looking for doesn't exist. Sorry about that.

Does anyone know what it is and or how to repair it?

Thanks!

Hello,

Try clearing your site's cache.
If that does not do the trick, try repairing your db's tables.