真是喝冷水都塞牙，申请个证书报错了，看看如下错误
Request Mode:
newreq - New Request
Disposition:
(never set)
Disposition message:
(none)
Result:
The RPC server is unavailable. 0x800706ba (WIN32: 1722)
COM Error Info:
CCertRequest::Submit: The RPC server is unavailable. 0x800706ba (WIN32: 1722)
LastStatus:
The operation completed successfully. 0x0 (WIN32: 0)
Suggested Cause:
This error can occur if the Certification Authority Service has not been started
最后一句话说明很简单，CA 服务器上启动服务吧，
登录一看，果然服务down了，启动，我再启动，还是不生效，看看错误提示：
Active Directory Certificate Services did not start: It Could not load or verify the current CA certificate. COE Lab Root CA Object was not found. 0x80090011 (-2146893807).
使用备份的CA恢复，能够重新启动了，
看看网上讨论这个问题还蛮多，不是私钥出问题就是证书出问题
只不过大多都是重新安装CA了事，谁让你平时不做CA 备份：），所以这里主要提醒的就是现在微软服务器用证书的会越来越多，定期备份CA 绝对是个好习惯，有空也可以参考这个KB，找微软要HOTFIX。
