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Please post the console log to pastebin.com; there is a button on the console window that does it for you and provides you a pastebin link to post here.
It looks like you're picking up a global Java argument (the second -Xmx).
Go to the 'Properties' of your Computer, then go to the 'Advanced' tab and click on 'Environmental Variables'. Scroll through the System Variables til you see one for Java and edit/delete it.