Error 01:  File does not exist
 Error 02:  File is not open for input
 Error 03:  File is not open for output
 Error 04:  File not Open
 Error 10:  Error in numeric format
 Error 20:  Operation not allowed on a logical device
 Error 21:  Not allowed in direct mode
 Error 22:  ASSIGN to standard files is not allowed
 Error 90:  Record length mismatch
 Error 91:  Seek beyond end of file
 Error 99:  Unexpected end of file
 Error F0:  Disk write error
 Error F1:  Directory is full
 Error F2:  File size overflow
 Error F3:  Too many open files
 Error FF:  File has disappeared