Cryptic MySQL Error on DROP TABLE

Ran across this fairly unhelpful error in MySQL today: InnoDB: Error: in ALTER TABLE `myschema`.`mytablename` has or is referenced in foreign key constraints which are not compatible with the new table definition. [Warning]: Invalid (old?) table or database name ‘#sql-a5c_8’ InnoDB: Error: table `myschema`.`mytablename` does not exist in the InnoDB internal data dictionary though MySQL is trying to drop […]