follow robdam1001 instructions, that should get it to work.
if not.
make sure you have your photos, contacts and apps backed up.
and erase all content and settings from your phone and do the jailbreak that WILL work.
now finished installing cydia, let it update itself, and go ahead and do a "restore from back up", i did this and i got everything back the way it was and cydia was working 100%