Here's the line:
ftp -s:D:\Admin\Scripts\ftp-put.txt >> D:\Admin\Script-logs\usan-ftp.log
Here's the content of "ftp-put.txt":
NB: I was not using scheduled task to run the job, I saved the command line in a .bat file and ran it. I mentioned it to say I can now use the .bat file in the task so it had nothing to do with access right.
Like I said earlier I don't have full understanding of why it wasn't running from the earlier location.