Mac 或 Windows 计算机(Mac or Windows computer) 无法识别您的外部硬盘驱动器或闪存驱动器(drive or flash drive)？这是一个常见问题，尤其是在Mac OS X(Mac OS X)、Windows 和 Linux(Windows and Linux)之间连接硬盘时。它也可能发生在单个系统上，它在很长一段时间内都可以正常工作，然后突然停止被操作系统(operating system)识别。
有时修复很容易，有时它有点复杂。在本文中，我将尝试通过Mac 和 Windows(Mac and Windows)上的不同解决方案来解决此问题。驱动器的格式化方式和使用的文件系统(file system)是驱动器无法识别的最常见原因。
分配驱动器号
另一个主要原因是驱动器根本无法被Windows 或 Mac(Windows or Mac)识别，因此根本不会出现在您的系统上。这通常是驱动程序或硬件的问题。为了确定您的问题是与格式化有关还是与无法识别有关，请转到 Windows中的磁盘管理或(Disk Management)OS X上的磁盘工具(Disk Utility)，查看驱动器是否显示在那里。
如果驱动器出现在此处，但不在Windows Explorer中，您可能需要为磁盘分配驱动器号。通常，Windows会自动执行此操作，但有时由于其他连接的设备，您的外部硬盘驱动器将被识别，但没有分配任何驱动器号。在磁盘管理(Disk Management)中，只需右键单击磁盘并选择更改驱动器号和路径( Change Drive Letter and Paths)。
为您的驱动器选择一个字母，您应该一切顺利。如果驱动器正在显示，但您收到有关需要格式化驱动器(drive needing)等的消息，请阅读下面的下一部分。
在Mac 上(Macs)，驱动器应自动出现在桌面上。如果没有，请转到Disk Utility并检查它是否出现在External标题下。
如果驱动器显示在此处，但不在OS X 桌面上(OS X desktop)，则单击急救(First Aid)以尝试修复驱动器。如果驱动器具有OS X无法识别的文件系统(file system)，则需要擦除它并使用FAT or HFS+对其进行格式化。
如果驱动器根本没有出现在“磁盘管理”或“磁盘工具(Disk Management or Disk Utility)”中，则说明您遇到了其他类型的问题。向下滚动(Scroll)到下面的未显示(Not Showing Up)部分。
格式化驱动器
在文件格式方面，大约 99% 的时间都在使用两种主要格式：Windows的FAT32和NTFS以及 Mac 的(NTFS) HFS+ (Mac OS Extended)扩展(Macs)）。现在OS X可以读取和写入FAT32格式的驱动器，但只能读取NTFS卷。
Windows在默认情况下甚至无法读取或写入HFS+格式的卷的意义上更糟糕。你可以让Windows来做，但你必须购买第三方软件。唯一的其他选择是格式化硬盘并使用FAT32 格式(FAT32 format)以获得最佳兼容性。
当您将HFS+格式化的驱动器连接到Windows时，您将收到一条消息，指出该驱动器需要格式化才能使用。
如果您看到此消息，仅表示Windows无法识别驱动器上的文件系统(file system)。确保(Make)将驱动器连接到适当的操作系统并(operating system and backup)在执行格式化之前备份您可能需要的所有数据。
那么，为了让您可以在多个操作系统上查看硬盘驱动器，最好使用什么格式呢？最兼容的旧格式(legacy format)是FAT32，但它将您的最大文件大小(max file size)限制为 4 GB 。您可以阅读我之前关于如何使用FAT32(FAT32)格式化外部硬盘的帖子。
如果您需要支持更大的文件，那么您应该使用exFAT格式。它更新并支持更大的文件，但仅适用于更新版本的OS X 和 Windows(OS X and Windows)。您必须运行OS X Snow Leopard (10.6) 或更高版本或Windows XP或更高版本。
在Windows中，除了NTFS 和 FAT32(NTFS and FAT32)之外，您还可以选择 exFAT 作为文件系统格式(file system format)。当您在OS X中使用磁盘工具(Disk Utility)格式化驱动器时，您还可以根据需要选择exFAT 格式(exFAT format)。
驱动器未显示
如果您将驱动器连接到计算机并且没有任何(computer and nothing happens)反应，则可能是以下几种情况之一：您的硬盘驱动器可能有问题，您的系统上没有安装正确的软件或驱动程序(software or drivers)，或者有一些东西无法正常工作操作系统(operating system)。让我们从一些常见问题及其解决方案开始。
Windows – 设备管理器
有时，旧驱动程序在连接到Windows(Windows)时会导致设备出现故障。您可以尝试通过首先转到命令提示符(command prompt)（Start 并输入(Start and type)CMD ）(CMD)并运行以下命令来解决此问题：
set devmgr_show_nonpresent_devices=1
完成后，打开设备管理器(Device Manager)（开始并输入(Start and type)设备管理器(device manager)），然后单击查看(View)-显示隐藏的设备(Show Hidden Devices)。
展开Portable Devices，右键单击任何灰显的项目并选择Uninstall。重新启动计算机并尝试再次连接硬盘驱动器。
除了便携式(Portable) 设备之外，如果设备在(Devices)Windows 资源管理器(Windows Explorer)中没有正确显示，您可以展开磁盘驱动器( Disk Drives)并尝试从那里卸载该设备。
Windows – USB 设备
如果您将USB 驱动器(USB drive)连接到Windows并收到USB 设备无法识别(USB Device Not Recognized)错误，请务必查看有关如何解决该特定问题的链接。Windows试图将故障归咎于设备，但这通常是Windows的问题。
USB 端口/辅助 PC
您还可以尝试将驱动器插入计算机上的另一个USB 端口(USB port)，以确保该特定端口没有问题。如果您要连接到USB 集线器(USB hub)，请断开它并尝试将驱动器直接连接到计算机。
此时，您可以真正判断问题是计算机还是硬盘驱动器的唯一方法是将驱动器连接到另一台计算机。如果驱动器(drive doesn)不能在另一台计算机上工作，则驱动器本身很可能有问题。
驱动工具
如果驱动器本身出现问题，您可以尝试从驱动器制造商(drive manufacturer)处下载诊断工具。几乎所有主要品牌，如希捷(Seagate)、西部数据(Western Digital)、东芝(Toshiba)等，都有这些诊断工具。
http://www.seagate.com/support/downloads/seatools/
Western Digital DataLifeguard Diagnostic
Fujitsu (Toshiba) Diagnostic Utility
您还可以阅读我之前关于检查硬盘驱动器错误的文章，以获取更多信息和更多测试硬盘驱动器的工具。如果驱动器损坏或有坏扇区，这些工具可以修复它。
USB 3.0 驱动器
如果您有USB 3.0外部硬盘驱动器，则必须考虑一些额外的注意事项。首先，确保您使用的是合适的电缆。我遇到了几个有这个问题的客户，并通过简单地使用不同的USB 电缆(USB cable)来解决它。所以在你放弃之前尝试几根电缆。
其次，您可能需要更新Windows中的驱动程序。再次(Again)，转到设备管理器(Device Manager)，展开通用串行总线控制器(Universal Serial Bus controllers)，右键单击文本中包含USB 3.0的控制器，然后选择更新驱动程序( Update Driver)。
电源问题
此类问题的唯一其他可能性是电源不足或硬盘驱动器完全故障(drive failure)。确保(Make)硬盘驱动器具有正确的外部电源适配器(power adapter)，并且驱动器正面的指示灯亮起且不是橙色或红色。此外，请尝试使用不同的电缆，因为有些电缆能够比其他电缆承载更多的电力。
希望本文能帮助您获得Windows 或 Mac(Windows or Mac)识别的外部硬盘驱动器。如果没有，请发表评论，我会尽力提供帮助。享受！
External Hard Drive Not Showing Up in Windows or OS X?
Mac or Windows computer not recognizing your extеrnal hаrd drive or flash drive? This iѕ a common problem, especially when connecting hard drives bеtween Mаc ОS X, Wіndows and Linux. It can also happen on a single system where it wаs working just fine for a long time and thеn suddenly stops being recognized by the operating systеm.
Sometimes the fix is easy and sometimes it is a bit more complicated. In this article, I’ll try to go through the different solutions on Mac and Windows for fixing this issue. How the drive is formatted and what file system is being used is the most common reason why drive is not recognized.
Assign Drive Letter
The other main reason is that the drive simply is not being recognized by Windows or Mac and therefore won’t even show up on your system at all. This is usually a problem with drivers or hardware. In order to figure out whether your problem is related to formatting or to not being recognized, go to Disk Management in Windows or Disk Utility on OS X and see if the drive shows up there.
If the drive shows up here, but not in Windows Explorer, you might have to assign a drive letter to the disk. Normally, Windows does this automatically, but sometimes because of other connected devices, your external hard drive will be recognized, but not have any drive letter assigned to it. In Disk Management, just right-click on the disk and choose Change Drive Letter and Paths.
Pick a letter for your drive and you should be good to go. If the drive is showing, but you’re getting messages about the drive needing to be formatted, etc., then read the next section below.
On Macs, the drive should automatically appear on the desktop. If not, go to Disk Utility and check to see if it appears under the heading External.
If the drive is showing here, but not on the OS X desktop, then click First Aid to try and repair the drive. If the drive has a file system not recognized by OS X, you’ll need to erase it and the format it using FAT or HFS+.
If the drive is not showing up in Disk Management or Disk Utility at all, you have some other type of problem. Scroll down to the Not Showing Up section below.
Format Drive
When it comes to file formats, there are a couple of major formats that are used about 99% of the time: FAT32 and NTFS for Windows and HFS+ (Mac OS Extended) for Macs. Now OS X can read and write to FAT32 formatted drives, but can only read NTFS volumes.
Windows is worse in the sense that it cannot even read or write to HFS+ formatted volumes by default. You can get Windows to do it, but you have to purchase third-party software. The only other option is to format the hard drive and use the FAT32 format for the best compatibility.
When you connect a HFS+ formatted drive to Windows, you’ll get a message stating that the drive needs to be formatted in order to be used.
If you see this message, it just means that Windows does not recognize the file system on the drive. Make sure you connect the drive to the appropriate operating system and backup any data that you might need before performing a format.
So what’s the best format to use so that you can see your hard drive on multiple operating systems? The legacy format that is most compatible is FAT32, but it limits you to only 4 GB for max file size. You can read my previous post on how to format an external hard drive using FAT32.
If you need support for bigger files, then you should use the exFAT format. It’s newer and supports much larger files, but only works with newer versions of OS X and Windows. You’ll have to be running OS X Snow Leopard (10.6) or higher or Windows XP or higher.
In Windows, you can choose exFAT as the file system format in addition to NTFS and FAT32. When you format a drive in OS X using Disk Utility, you can also choose the exFAT format if you like.
Drive Not Showing Up
If you connect the drive to the computer and nothing happens, one of several things could be going on: your hard drive might have a problem, the correct software or drivers are not installed on your system, or there is something not working properly with the operating system. Let’s start with some common problems and their solutions.
Windows – Device Manager
Sometimes old drivers can cause a device to malfunction when connected to Windows. You can try fixing this by first going to the command prompt (Start and type in CMD) and running the following command:
set devmgr_show_nonpresent_devices=1
Once you do that, open Device Manager (Start and type in device manager) and then click on View – Show Hidden Devices.
Expand out Portable Devices, right-click on any items that are grayed out and choose Uninstall. Restart your computer and try to connect the hard drive again.
In addition to Portable Devices, you can expand out Disk Drives and try to uninstall the device from there if it is not showing up properly in Windows Explorer.
Windows – USB Device
If you connect your USB drive to Windows and get a USB Device Not Recognized error, make sure to check out the link on how to fix that particular problem. Windows tries to blame the device for malfunctioning, but it’s normally a problem with Windows.
USB Ports/Secondary PC
You can also try plugging the drive into another USB port on the computer to make sure it’s not a problem with that particular port. If you are connecting to a USB hub, disconnect that and try to connect the drive directly to the computer.
The only way you can really tell if the problem is with the computer or the hard drive at this point is to connect the drive to another computer. If the drive doesn’t work on another computer, it’s highly likely something is wrong with the drive itself.
Drive Tools
If it appears that there is a problem with the drive itself, you can try to download the diagnostic tools from the drive manufacturer. Just about all the major brands like Seagate, Western Digital, Toshiba, etc., have these diagnostic tools.
http://www.seagate.com/support/downloads/seatools/
Western Digital DataLifeguard Diagnostic
Fujitsu (Toshiba) Diagnostic Utility
You can also read my previous post on checking your hard drive for errors for more information and more tools to test hard drives. If the drive has become corrupt or has bad sectors, these tools can fix it.
USB 3.0 Drives
If you have a USB 3.0 external hard drive, there are a couple of extra considerations you have to take into account. Firstly, make sure you are using an appropriate cable. I’ve run into several clients that had this problem and fixed it by simply using a different USB cable. So try out several cables before you give up.
Secondly, you might need to update the driver in Windows. Again, go to Device Manager, expand Universal Serial Bus controllers, right click on the one that has USB 3.0 in the text and choose Update Driver.
Power Issues
The only other possibilities with this type of problem are lack of power or complete hard drive failure. Make sure the hard drive has the correct external power adapter and that the light on the front of the drive is turning on and is not orange or red. Also, try using different cables as some are able to carry more power than others.
Hopefully, this article will help you get your external hard drive recognized by Windows or Mac. If not, post a comment and I’ll try to help. Enjoy!
