mac assistant can't be opened

hi all...

first thing first i am new to all this so plz accept my apologise if i am doing something wrong...

have downloaded mac assistant rt i double click on it from my desk top and a box reading “MacAssistant RT” can’t be opened because it is from an unidentified developer.

help plz

HAVE SORTED IT NOW.....

Hi mate, any chance you could let me know how you sorted this? I'm having the same problem!

2013-12-28 17:05#151693 olip93 : Hi mate, any chance you could let me know how you sorted this? I'm having the same problem!

http://www.imore.com/how-open-apps-unidentified-developer-os-x-mountain-lion