Cydia won't open on iPad 3 5.1.1

Hi I have just jail broken my iPad 3 with greenpoisi0n but the cydia app will not open at all. I reset and erased all settings again just like before jailbreakng it to do it again. Then plugged it in to jailbreak but it is swing it already jail broken untether detected, cydia app is still there but again won't open. Help me please

After alot of searching to figure out a way how to get it to work with out restoring i found nothing. Restored it to my mac for the first time which took about 3 hours and jailbroke again works perfect. For anyone out there who may have the same issues