Within the report definition, 4GL generated an SQL statement to save rows into a temporary table, but the temporary table could not be created. Probably no disk space is left in the database, or you already have a table in your current database with the same name as the temporary table that the report definition is attempting to create as a sorting table.
Another possible cause is that the report name is too long. It should be 16 characters or fewer if your database server allows only table names up to 18 characters long, to leave room for the "t_" prefix.
The sorting table is named "t_reportname". For example, a report named "order_rpt" would name its sorting table "t_order_rpt". Users should avoid beginning table names with "t_".
Another possible cause of this error with some database servers is that you have exceeded an operating-system limit on open files.
Look for other error messages that might give more details.