Is this an issue with a new installation?
Did you upgrade ? / what sequence etc..
You can try this one, it will require that you reinfuse your infusions, but they should not take damage.
Open a costume page , name it anything
Then paste this & run a preview & try to infuse something.
<?php
$result = dbquery("DROP TABLE IF EXISTS ".$db_prefix."infusions");
$result = dbquery("CREATE TABLE ".$db_prefix."infusions (
inf_id SMALLINT(5) UNSIGNED NOT NULL AUTO_INCREMENT,
inf_title VARCHAR(100) NOT NULL DEFAULT '',
inf_folder VARCHAR(100) NOT NULL DEFAULT '',
inf_version VARCHAR(10) NOT NULL DEFAULT '0',
PRIMARY KEY (inf_id)
) TYPE=MyISAM;");
?>