Can't Install, NSIS Error

i can not install wimamp or anything else
it says

NSIS ERROR
Installer corrupted or incomplete. This could be the reslut of a failed download or corruption from a virus. If desperate try the /NCRC command line switch(not recommended)" does anyone know how to get rid of this,please help

Well...as the message say: The installer is corrupted.
Try download the file again.