DEFINE VARIABLE vIFileName  AS CHARACTER INITIAL "c:\work82\escalation.csv" NO-UNDO.
DEFINE VARIABLE vOk         AS LOGICAL NO-UNDO.

SYSTEM-DIALOG GET-FILE vIFileName
  TITLE "Select SysErrCodes Input File"
  FILTERS "Comma Separated (*.csv)" "*.csv"
  INITIAL-FILTER 1
  MUST-EXIST
  UPDATE vOk.
IF NOT vOk THEN UNDO, RETRY.