I would of course assume the answer is no, however I wanted to confirm this is so, in case there could be a chance that I might lose some files on accident.

  • 1
    Of course the answer is yes: you should always have a backup! But that has absolutely nothing to do with installing Ubuntu: You should have a backup if you're using your PC for anything, because Backups is what saves you when you accidentally delete a file, or your hard drive or SSD fail, if some malware encrypts your data, or your cat pushes a vase of whater into your computer. – Marcus Müller Jun 19 '19 at 7:08

Although installing Ubuntu alongside Windows in a dual-boot configuration shouldn't, and typically doesn't, cause any data loss, it is nonetheless a very good idea for you to have a backup, at least of your documents and any other important files, that is, files you would be upset if you lost.

I'd say the three chief reasons for this are that:

  1. There's a small risk of data loss when resizing and moving partitions and editing partition tables. This was bigger decades ago, but it's not zero today. In particular, it's likely to occur if the computer suddenly turns off during the operation, which could happen in a power failure.
  2. There's a small risk you may make a mistake while installing Ubuntu. The installer tries to warn about operations that could cause data loss, but it gives a lot of information, and in practice people sometimes do accidentally tell it to overwrite their existing systems. (Furthermore, this risk does not drop to zero even among very experienced users.)

The popular question How do I recover my accidentally lost Windows partitions after installing Ubuntu? is probably an example of one of those (though I'm not certain which).

Far less serious than those first two situations but also more likely:

  1. Sometimes installing Ubuntu temporarily prevents other operating systems, including Windows, from booting. This shouldn't happen and usually doesn't, but it sometimes does. This is temporary in the sense that you can fix it, and also in the sense that it's still possible to access the data, whether or not you fix it. But it's frustrating, and not being sure if you've lost data when it first happens is quite unpleasant.

Those are the reasons to have a backup--at least of your documents and other important files--when you're installing Ubuntu in a dual-boot configuration. You should, as Marcus Müller says, always have backups of your important stuff anyway, regardless of what operating system you're using. Data loss can occur at any times. Hard disks (even SSDs) don't last forever and can lose data even before they fail, and various causes ranging from malware to user error can cause files to be accidentally deleted or modified. If you already have a backup, then (a) good, and (b) I recommend making sure it's up to date before installing Ubuntu.

Once Ubuntu is installed, you should continue maintaining backups of your documents and important files, no matter where you store them. For information on some backup strategies and how to apply them in Ubuntu, see What's a good back-up strategy for 1 desktop PC?

  • Thanks I was worrying about something like that, have you ever encountered any of these scenarios? – Code4life Jun 19 '19 at 7:40
  • @Code4life Personally, not with the automatic option to install alongside another OS. I usually (re)partition manually and I've made mistakes a few times. I've had backups and never lost anything important. Also, years ago GParted crashed moving a partition; I think it was a damaged filesystem triggering a (now fixed) bug. I haven't had or heard of such issues since. My power once failed as I foolishly repartitioned with no good backup. Amazingly, nothing was lost! Yet most of my advice above isn't from personal experience. I'll try to add links to relevant posts about data recovery soon. – Eliah Kagan Jun 20 '19 at 23:28

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.