Windows提供了加密文件的方便方法，但是一但删除帐户或重装系统，加密后的文件将再也无法解密，直接导致文件“丢失”。本文提供了一个对EFS解密的方法，值得学习。-Windows provides a convenient document encryption methods, but a deletion of accounts or reinstall system, encrypted files will no longer declassified documents directly led to the "lost." This paper provides one pair of EFS declassified, worth learning.