The question does not mention the exact need:
IF you need to store the MDB or XLS file on the iSeries disks "as is" it is very easy to FTP from the client to the server. The FTP script is like this (ie ftp.txt):
lcd localdir
cd /remotedir
bin
put xls
quit
See Microsoft's Knowledge Base for the exact instruction on using FTP in batch from windows.
This method requires the FTP port on the iSeries.
This was first published in September 2004