Hi Prabhu,
Obviously this FM checks the storage category and file location in database so if it does not exist it will give you an error so your above approach will be a correct approach.
Check it like this
** Check in original 1 simultaneously in the SAP Database
REFRESH lt_files.
CLEAR lt_files.
lt_files-storagecategory = 'SAP-SYSTEM'.
lt_files-docfile = 'c:\temp\drawing.txt'.
lt_wsapplication = 'TXT'.
APPEND lt_files.
Thanks