My Unity Desktop Broken because of MyUnity

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http://askubuntu.com – I've just installed MyUnity in Ubuntu 12.04 and changed the system font style but suddenly it crashed. I tried to boot it again but it crash again and again. So I log in via guest and remove MyUnity from software center but when I tried to log in via admin user, it crashed again! How do I solve this problem? (HowTos)