The database server created a temporary file in the directory specified by the DBTEMP environment variable (or /tmp by default on UNIX systems) but encountered an error when it tried to read the file back. Check the accompanying ISAM error code, and look for operating-system error messages that might give more information. Possibly a hardware failure occurred, or possibly another user erased the temporary file accidentally. Since Version 5.01, the IBM Informix SE database server uses the DBTEMP environment variable, but IBM Informix Dynamic Server and IBM Informix OnLine Dynamic Server do not.