It can be your downloaded file to be corrupted, sad to say it but chrome tends to corrupt files due to the built in check for virus crap they have....
I'm affraid u might need to download the client again if u can.
try using torrent or the direct link into a program, something like: JDownloader (free) or IDM (needs to buy or crack). those r only examples, i suppose using any other program is fine ^^ torrent works fine too, program to downlaod torrents is free aswell.