Problem loading .elf file

HI...

I am trying with the DE2_115_WEB_SERVER_RGMII_ETEN0

I download the .sof file successfully and when trying to programming flash with ro_zipfs.zip it works and shows that "Done loading flash setting files".

But when trying to programming .elf file it shows "empty flash file cannot be programed"

Then i tried to run the .bat file in the /demo_batch/web_server.bat but is also shows error..

Please help me.. is there any solution......