Can't convince my 2011 i7 MBP to boot from USB?

currently using ssd , hd combo have no optical drive, obviously.

ssd split 2 partitions - 1 has windows 7 on it, need upgrade win7-64.

i've made guid usb drive , restored w7 install image onto can't boot drive no matter do! have tried using refit regular boot device selection on startup, no luck.

else dealt this?

 

windows can't booted external hdd, though windows 8 shall include feature, finally.

 

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