Problems Installing

I downloaded SmartFTP, and I have the icon on my desktop saying SFTPfull.exe. When I go to double click on it to install and run SmartFTP, however, it comes up with this message:

NSIS Error

The installer you are trying to use is corrupted or incomplete.
This could be the result of a damaged disk, a failed download or a virus.

You may want to contact the author of this installer to obtain a new copy.

It may be possible to skip this check using the /NCRC command line switch

(NOT RECOMMENDED).

Any way to fix this and download and install properly?