10 REM FILE TEST
20 OPEN 1, 8, 4, "TESTFILE,SEQ,W"
30 IF ST <> 0 THEN PRINT "FILE ERROR"
40 IF ST = 0 THEN PRINT "FILE EXISTS"
50 CLOSE 1

BAD SUBSCRIPT

ERROR: #L0L9G6MC5WUFW29CT4UBB6U3RVYCEG8T