Transaction Log Errors in SEv5.03

Has anybody had any experience with the following SE errors -346 Could not update a row in the table. While processing an UPDATE, the database engine received an unexpected error. Check the accompanying ISAM error code for more detailed information on the cause. Possible causes include hardware errors and locking conflicts. -121 ISAM error: cannot write log record The ISAM processor is trying to add a record to the transaction log and has received an error from the operating system. One probable cause is that the disk is full. Look for operating system error messages that may give more information. The transaction log file can grow quite large. In order to reduce its size you must do two things. First, make a backup copy of the data file (C-ISAM) or all database files (SQL). Second, make the transaction log file an empty file. If these steps are performed routinely, the size of the log file can be controlled. We have tried all the above like clearing the log and even bcheck-ing the table in policy. The table has 28000 +- and we want to update 1 column where col = blah and column = blah . The update should have modified 17000+- recs but it falls over in dbaccess with the above messages. The only thing we have not done is drop the log itself. We have also looked at the disk space and the NPROC & NFILE. To drop/delete the trans log is it safe to remove the row for tabid=0 from the systables as user informix ? Any Ideas Noel SE v5.03 4GLv4.14 SCO 3.2v4.2