If you don't want to splash out on a Bluetooth dongle, check if your PC has an Infra Red port as an alternative wireless connection.
If it does, activate the Infra-Red port on your K700i, then hold the phone close to your PC's IR port, Windows should automatically detect it, and you can then select & send the file(s) you want to the phone.
If it's a big file I would go with the USB cable.