This internal error message does not refer to a problem with a SERIAL or SERIAL8 or BIGSERIAL column in a table that you defined. The database server uses unique integer values for many purposes (for example, the table ID number for a new or altered table). An internal error has made it impossible to generate a new, unique number. For example, in host systems that use files for locking, something might have prevented the creation of a lock file. Check the accompanying ISAM error code for more information. If the error recurs, note all circumstances and contact IBM Informix Technical Support.