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Can I Back Up Files to Save Space?

Question: Is it OK to backup files on Windows XP to free more space?

Well, the answer is yes, but your question raises a number of very important issues about backing up and deleting files that I want to address.

If you’re using your backup program as a glorified copy program, that’s OK, but I wouldn’t call it backing up. Remember the golden rule: if there’s only one copy of something, it’s not backed up.

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The principles of backing up

If you copy a file from your machine to somewhere else and you call that backing up, that’s good. You have two copies – one on the machine and another in your backup.

But if you then delete the file on your machine, it’s no longer backed up. You are left with only one copy – you may call it your “backup” copy, because you’ve placed it on what you consider your “backup ” media, but if it’s the only copy, then it’s not backed up.

Even if it’s part of a larger backup – say a collection of files, or even part of a system image backup – if it’s the only copy of that file, then it could be lost forever if something happens to that larger backup.


If all you’re doing is moving, not copying, files, then I strongly recommend that you don’t think of this process as backing up – even if you’re using backup software to do it.

Remember that the whole concept of backing up is making sure that you have multiple copies of whatever it is that you don’t want to lose. If you’re just moving files off of your hard disk on Windows XP to free space, then you’re not really backing up, you’re just moving files around. That’s OK, as long as those files are somehow backed up in addition to whatever you end up with.

Deleting files and backing up

Now, let’s talk about deleting files.

Before you delete anything from your machine, make sure that they would still be backed up after you delete. By that I mean you have at least three copies in some form before you delete anything. Then, when you delete file from your machine you’ll still be left with two: one backing up the other.

My other recommendation is that to the best you can you make sure that the files that you’re about to delete are ones that you truly don’t need. It’s very simple to delete files, but it can cause problems if you delete the wrong files. In a benign scenario, deleting the wrong files does nothing – you just simply don’t have that file anymore.

But on the other hand, some files are important. Some may be related to the data you care about. Applications may need them to run. Sometimes even Windows needs these files to run. And yes, it’s absolutely possible to delete the wrong files and cause Windows to stop working.

So, determine which files are safe to delete before you do and have a full image backup of your entire machine to give you a little bit of flexibility. If you happen to delete the wrong file, then you can just restore the machine from your backup and start over.

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2 comments on “Can I Back Up Files to Save Space?”

  1. A bit of terminology for the questioner.
    It sound like you are really asking if you can move something to “off line” storage instead of backing it up. As Leo said, backups are a second copy.

    Many people just use a usb hard drive to move some of their less used files and when you unplug it, it becomes off line. You can then include the usb drive in with a backup program to make sure you don’t loose the files.

    If you just use the file copy or move command to get the files on the portable drive instead of being tempted to do it with a backup program, you can use them at any time by just plugging the drive in and opening the files.


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