您可能听说过您意外删除或丢失的文件可以恢复。互联网上有很多应用程序可以做到这一点。您甚至可能已经或多或少地尝试了一些文件恢复应用程序。(file recovery apps)但是，您有没有问过自己为什么会这样？为什么删除的文件可以恢复？阅读本指南以找到这个简单问题的答案：
删除文件时会发生什么？
当您从硬盘驱动器中删除文件时，您可能会认为它永远消失了。但是，即使您从回收站(Recycle Bin)中删除它，事实是它并没有从存储中物理擦除。
每个文件都由许多信息组成。当您删除一个文件时，构成它的所有这些位都不会被物理擦除，它们会继续保存构成该文件的信息。而不是物理删除文件，这可能需要大量时间，特别是如果这些文件很大，操作系统(operating system)只会将删除的文件标记为可用空间。
你(Are)想知道操作系统(operating system)是如何做到的吗？答案很简单：要知道文件在您的驱动器、Windows或其他操作系统(operating system)上的位置，为它们分配指针。当您删除一个文件时，Windows通过仅删除其指针而不是其他任何内容来将其标记为可用空间。文件的内容仍然存在，物理上。
这也意味着下次您或操作系统(operating system)创建新文件时，该新文件可以保存在硬盘驱动器上任何可用空间的顶部。曾经是您删除的文件的存储空间(storage space)被操作系统(operating system)视为可用于存储新文件的可用空间。如果曾经是文件的空闲空间碰巧被操作系统(operating system)用来存储新数据，则原始删除文件的内容将被覆盖。在这种情况下，恢复已删除文件的机会很小。
如何从驱动器中恢复已删除的文件？
现在您知道已删除的文件并未真正从驱动器中删除。它们仅被标记为可用空间。找回您意外删除或丢失的文件是可能的。为此，您必须使用专门的应用程序。此类程序可以在您的驱动器上找到已删除文件的内容并重新分配其指针或复制其内容并在您选择的其他存储位置重新创建文件。换句话说，文件恢复应用程序(recovery apps)可以告诉Windows在哪里可以找到已删除的文件，然后恢复它们。
如果您正在寻找恢复丢失文件的方法，这些文章是一个很好的起点(starting point)：
- 如何使用Recuva恢复已删除的文件（从分区、记忆棒(memory stick)、存储卡(memory card)等）
- 哪些是最好的免费文件恢复(file recovery)工具？比较 5 个最受欢迎的应用程序
为什么有些已删除的文件无法恢复，即使您使用的是优秀的文件恢复工具(file recovery tool)
恢复丢失的文件并不总是可能的！如果Windows覆盖已删除文件占用的空间，则无法再恢复原始文件。那是因为该原始文件的内容不再存在。新信息(New information)存储在其内容之上，因此旧信息被销毁。
尝试恢复已删除文件时要注意什么
当您删除文件并尝试恢复它们时，您应该始终记住两件事：
- 停止(Stop)使用找到这些文件的硬盘驱动器或分区(drive or partition)
- 尝试尽快恢复已删除的文件
当您错误地删除文件并继续使用找到它们的硬盘驱动器或分区(drive or partition)时，它们很可能被新文件覆盖并且不再可恢复。即使您没有在该驱动器或分区(drive or partition)上复制或创建新文件，操作系统(operating system)也可能会使用您曾经删除过的文件的可用空间来创建临时文件或交换文件。(swap file)因此，您不应该浪费时间并尝试尽快恢复已删除的文件。
此外，如果您在找到已删除文件的同一驱动器上安装文件恢复应用程序(file recovery app)，则安装可能会覆盖全部或部分已删除文件。这使它们无法恢复。文件恢复应用程序(recovery apps)应该安装在另一个分区上，或者它们应该在USB 记忆(USB memory)棒上的便携式版本中使用。
结论
现在您知道已删除的文件并没有真正从您的硬盘中删除，至少在其他文件覆盖其数据之前是这样。这就是为什么可以使用专门的文件恢复应用程序(recovery apps)来恢复它们。如果您对此事有任何疑问或需要我们的帮助，请使用下面的评论部分告诉我们。
Simple questions: What happens to deleted files? Why can you recover some of them?
You have probably heard that the filеs that you accidentally delete оr have lost, can be recovered. There are many apps on the internet that can do it. You might have even tried some file recovery apps with more or less success. However, did you ask yourself why that is possible? Why can deleted fіles be recovered? Read thіs guide to find the answer to this ѕimple question:
What happens when you delete a file?
When you delete a file from a hard drive, you might think that it is gone forever. However, even if you delete it from the Recycle Bin, the truth is that it is not physically erased from the storage.
Every file is made out of many bits of information. When you delete a file, all those bits that form it are not physically erased, and they continue to hold the information that makes the file. Instead of physically deleting files, which can take a significant amount of time, especially if those files are large, the operating system only marks the deleted files as free space.
Are you wondering how the operating system does that? The answer is simple: to know where files are found on your drives, Windows or other operating systems, assigns them pointers. When you delete a file, Windows marks it as free space by removing only its pointer, nothing else. The content of the file is still there, physically.
This also means that the next time you or the operating system creates a new file, that new file can be saved on top of any part of the free space on the hard drive. The storage space that was once the file you deleted is seen by the operating system as free space that can be used for storing new files. If the free space that was once a file happens to be used by the operating system to store new data, the content of the original deleted file is overwritten. In that case, there is little chance to recover the deleted file.
How do you recover deleted files from your drives?
Now you know that deleted files are not truly removed from your drives. They are only marked as free space. Getting back the files you deleted or lost by accident is possible. To do that, you have to use specialized apps. Such programs can find the contents of the deleted files on your drives and reassign their pointers or copy their content and recreate the files in other storage locations that you choose. In other words, file recovery apps can tell Windows where to find it the deleted files and then recover them.
If you are searching for ways to recover files you lost, these articles are a good starting point:
Why some deleted files cannot be recovered, even if you are using an excellent file recovery tool
Recovering lost files is not always possible! If Windows overwrites the space that a deleted file was occupying, the original file can no longer be restored. That is because the content of that original file is just not there anymore. New information was stored over its content, so the old information was destroyed.
What to be careful for when attempting to recover deleted files
There are two things you should always remember when you have deleted files, and you are attempting to recover them:
- Stop using the hard drive or partition on which those files were found
- Attempt to recover the deleted files as quickly as possible
When you delete files by mistake and continue using the hard drive or partition on which they were found, there is a significant chance that they are overwritten by new files and no longer recoverable. Even if you do not copy or create new files on that drive or partition, the operating system might create temporary files or a swap file using the free space that was once a file you deleted. So, you should not waste time and try to recover the deleted files as quickly as possible.
Also, if you are installing a file recovery app on the same drive on which the deleted files were found, the installation might overwrite all or part of the deleted files. That renders them unrecoverable. File recovery apps should be installed on another partition, or they should be used in their portable version, on a USB memory stick.
Conclusion
Now you know that deleted files are not indeed removed from your hard drives, at least until other files overwrite their data. That is why they can be restored using specialized file recovery apps. If you have any questions on this matter or if you need our help, use the comments section below to let us know.
