UBB.threads PHP Forum Software Community Forums UBB.threads 7 Version 7 Support Error editing an old post

I'm trying to edit an older post, and I get the following error when I try to submit the changes:

We encountered a problem. The reason reported was
Script: /hermes/bosoraweb079/b553/ipg.campinnforumcom/ubbthreads/scripts/modifypost.inc.php
Line#: 391
SQL Error: Incorrect key file for table './ubb/ubbt_POSTS.MYI'; try to repair it
SQL Error #: 126

Any ideas?