昨天4.21已越狱想升4.3.3，但是始终升级失败提示“发生未知错误3194” 查了好多帖子，有说在hosts文件中加入74.208.10.249 gs.apple.com的，添加后升级，失败！ 有说在hosts文件中删除74.208.10.249 gs.apple.com的，删除后升级，失败！ 把hosts文件修改成只有74.208.10.249 gs.apple.com一行的，3194。 把hosts文件中都删除掉的，3194 反复折腾，重启电脑，itunes，还是3194、3194、3194、3194.。。。。。。 最后万般无奈，实在是没有办法了，想想把hosts文件恢复成默认行不行？ 恢复后，奇迹出现了，折腾了半天不能升级的一次升级成功！ 送上hosts默认文件，希望对出现此问题的锋友有所帮助！ # Copyright (c) 1993-2009 Microsoft Corp. # # This is a sample HOSTS file used by Microsoft TCP/IP for Windows. # # This file contains the mappings of IP addresses to host names. Each # entry should be kept on an individual line. The IP address should # be placed in the first column followed by the corresponding host name. # The IP address and the host name should be separated by at least one # space. # # Additionally, comments (such as these) may be inserted on individual # lines or following the machine name denoted by a '#' symbol. # # For example: # # 102.54.94.97 rhino.acme.com # source server # 38.25.63.10 x.acme.com # x client host # localhost name resolution is handled within DNS itself. # 127.0.0.1 localhost # ::1 localhost