无法使用此iphone，因为没有安装必需的软件。请运行iTunes安装器来移除iTunes，然后安装64位版本的iTunes。
This iPhone cannot be used because the required software is not installed. Run iTunes Installer to remove iTunes, then install 64-bit version of iTunes
遇到了这个问题，网上也有很多解决办法，一般是删了重装，可是有些人却还是不行。可以参考苹果官方的办法：https://support.apple.com/zh-cn/HT204275
如果链接打不开可以看这个： http://www.caojunfei.com/?p=3442
反正就是先删除相关程序，有顺序的。
卸载顺序：
1、iTunes
2、QuickTime
3、Apple Software Update
4、Apple Mobile Device Support
5、Bonjour
6、Apple 应用程序支持
7、iCloud
不过遗憾的是，试了这些方法并没有什么用。可能再找其它办法了。
网上找到以下方法：
“This iPhone cannot be used because the required software is not installed. Run iTunes Installer to remove iTunes, then install 64-bit version of iTunes.”
Let’s try a standalone Apple Mobile Device Support install. It still might not install, but fingers crossed any error messages will give us a better idea of the underlying cause of why it’s not installing under normal conditions.
Download and save a copy of the iTunesSetup.exe (or iTunes64setup.exe) installer file to your hard drive:
http://www.apple.com/itunes/download/
Download and install the free trial version of WinRAR:
Right-click the iTunesSetup.exe (or iTunes64setup.exe), and select “Extract to iTunesSetup” (or “Extract to iTunes64Setup”). WinRAR will expand the contents of the file into a folder called “iTunesSetup” (or “iTunes64Setup”).
Go into the folder and doubleclick the AppleMobileDeviceSupport.msi (or AppleMobileDeviceSupport64.msi) to do a standalone AMDS install.
(If it offers you the choice to remove or repair, choose “Remove”, and if the uninstall goes through successfully, see if you can reinstall by doubleclicking the AppleMobileDeviceSupport.msi again.)
Does it install (or uninstall and then reinstall) properly for you?
If instead you get an error message during the install (or uninstall), let us know what it says. (Precise text, please.)
大概意思就是用rar解压 iTunes6464Setup.exe，然后找到里面的AppleMobileDeviceSupport.msi (or AppleMobileDeviceSupport64.msi) ，然后安装。我也安装了，发现这个东西根本安装不了，安装一半就回滚了，最后提示：
“Apple Mobile Device Support wasn’t installed on your computer. The installer encoutered errors before Apple Mobile Device Support could be configured. Your system has not been modified. To retry these operations at a later time, please run the installer again.”
拿这个错误提示去搜索，也找到相应的答案了：
Just in case, try right-clicking on the AppleMobileDeviceSupport64.msi and selecting “Run as administrator”. Any better luck with the install?
意思是右击以管理员权限运行，不过发现TMD右击后根本没有 “以管理员权限运行”的菜单。再搜索了下，有用命令行安装的，见下面：
If you want to generate log files try one of the following commands. These have both the .msi files and the output logs located at the root of the C: drive but you can edit the paths to taste. The second option switch is slash el star vee and generates a verbose output log.
msiexec /i “C:\AppleMobileDeviceSupport.msi” /l*v “C:\Log_AMDS.txt”
msiexec /i “C:\AppleMobileDeviceSupport64.msi” /l*v “C:\Log_AMDS64.txt”
不过命令行运行了 msiexec 提示没有这个命令，然后搜索了下C盘，发现在C:\Windows\SysWOW64目录下有这个文件，如果真的没有的话，就网上下载个msiexec了。于是以管理员权限运行了cmd,进入C:\Windows\SysWOW64，然后执行 msiexec /i “C:\AppleMobileDeviceSupport64.msi” /l*v “C:\Log_AMDS64.txt”,这是也跳出了安装窗口，下一步后，还是那样，安装失败，回滚了。在安装itunes时，如果仔细看的话，在中间也会出现次回滚，其实就是这个安装包在回滚。
打开C:\Log_AMDS64.txt 搜索了下error,里面有好多error,没办法一个一个找，发现以下错误信息：
DIFXAPP: INFO: Installing INF file ‘C:\Program Files\Common Files\Apple\Mobile Device Support\NetDrivers\netaapl64.inf’ (Plug and Play).
DIFXAPP: INFO: Could not open file C:\Windows\System32\DriverStore\FileRepository\netaapl64.inf_amd64_neutral_56f23639c9617984\netaapl64.inf. (Error code 0x3: 系统找不到指定的路径。)
DIFXAPP: ERROR: PnP Install failed. (Error code 0x3EE: 文件所在的卷已被外部更改，因此打开的文件不再有效。)
DIFXAPP: INFO: Attempting to rollback …
DIFXAPP: INFO: No devices to rollback
好像是没有netaapl64.inf，于是网上搜索了下 “C:\Windows\System32\DriverStore\FileRepository\netaapl64.inf_amd64_neutral_56f23639c9617984\” 确实有相关答案
- 以64位系统示例，使用winrar打开 iTunes安装文件，释放出Applemobiledevicesupport6464.msi
- 使用Universal Extractor工具将上述文件（Applemobiledevicesupport6464.msi）再次释放
- 进入C:\Windows\System32\DriverStore\FileRepository，创建名称为“netaapl64.inf_amd64_56f23639c9617984”的目录。
- 回到Universal Extractor(网上下载个)释放出的文件目录，\common files\apple\Mobile Device Support\NetDrivers, 该目录下有4个驱动文件，copy至步骤4建立的目录内。重新运行iTunes安装文件，大功告成。
- 如果上述方法无效，可能非64位系统，请参见参考链接，了解原理，找到所需文件及目录，将步骤4-5重新执行。
照着试了下，果然成功了。
总结：看安装错误提示，就是因为找不到netaapl64.inf_amd64_neutral_56f23639c9617984\netaapl64.inf 这个文件，至于为什么也没弄清楚，然后手工把相关的这个文件复制到相应的目录里，就成功了。
相关参考链接：
https://discussions.apple.com/thread/3847504?tstart=0
https://discussions.apple.com/thread/6193927?start=15&tstart=0
https://discussions.apple.com/thread/4815371?start=0&tstart=0
http://jingyan.baidu.com/article/8065f87f955d47233124988f.html
https://support.apple.com/zh-cn/HT204275
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