I read on another forum that the problem could have to do with Melodyne. They said to delete the Melodyne rewire files from the propellorhead folder in root/library/app support/. So I deleted them to the Trash (but did not empty it) and relaunched Logic. Amazingly it loaded.
就是把系统根目录下的LIBRARY目录下的APPLICATION SUPPORT里的REWIRE文件都删除。。。就可以了