Can't Open on MAC

[Paul Carini]

I am using OSX 10.8.5 and cannot open my downloaded gnucash file.  My attempts lead to a "verifying "gnucash" process after which the gnu cash icon flashes in the dock and the warning appears "this is an application downloaded from the internet, do you want to open it?".  When I click on "open", the flashing icon in the dock disappears and all is dead.  I really want to try this software; it sounds like it is close to the old version of Quicken which was great but no longer supported by MAC Mt Lion.  Hope someone can help me open this application.  Thanks

Paul