在Xcode真机调试开发过程中，无论是使用个人证书或者是企业证书，经常会遇到这样的问题：The certificate used to sign "XXX" has either expired or has been revoked. An updated certificate is required to sign and install the application.刚开始在key里删除证书，在Xcode中fix一下，好像问题也不大。但是最近频发发生这样的事情，有时候需要耗费很久才能在搞定。后来在stack overflow找到一个帖子，是这样解决的：http://stackoverflow.com/questions/36689116/certificate-has-either-expired-or-has-been-revoked

First of all clean the project by holding Shift(⇧)+Command(⌘)+K or Select Product > CleanThenGo to XCode Menu> PreferenceSelect Account > Team > View DetailsSelect any Provisioning profile from Provisioning Profiles listRight click > Select Show in Finder. Then you will see all lists of provisioning profilesSelect all provisionaling list from the folder and move it to trashDownload All provisioning profiles by clicking Download All below Provisioning Profile lists.Now, Run again and it should Work!