How to uninstall Windows 10, Windows 8.1, Windows 7 or any other version
Some of our readers have sent us messages asking how they can remove the test versions of Windows 10 for Insiders which they installed or even older versions of Windows, such as Windows 7 or Windows 8.1. It does not matter what version of Windows you have, the procedure for uninstalling all of them is the same, and we share it in this article. We cover two different situations: how to remove a version of Windows when you have multiple installations of Windows on your computer and how to remove Windows when it is the only operating system installed. Let's get started:
How to remove one version of Windows from a dual or multi boot computer
Let's assume you have installed Windows 10 in a dual-boot setup with Windows 7. Let's say that you want to remove the older Windows 7 and install Windows 8.1 instead or use the space occupied by Windows 7 for something else. How do you do it?
Step 1. Backup your data
First, make sure that you backup any important data you have on the drive where the Windows version you want to remove is installed. You lose that data if you do not back it up now, while that operating system exists and works well.
Step 2. Remove the boot entry for the Windows version that you want to remove
It is time to remove the boot entry for the Windows operating system that you want to remove. In our example, that is Windows 7. Do this from the version of Windows that you want to keep. For us, that is Windows 10.
Boot to the operating system that you want to keep and start the System Configuration tool. A quick way to launch it is to use the Run window. Simultaneously press the Windows + R keys on your keyboard and, in the Run window that opens, enter the command msconfig. Press Enter or click OK and the System Configuration tool opens.
We use the System Configuration tool because it is available in all Windows versions. If you prefer, you can also use any other boot manager tool, but make sure that it is compatible with all the operating systems that you have installed. If you use System Configuration, open it and go to the Boot tab.
On the Boot tab, check if the version of Windows you are about to remove was set as the default boot operating system. If it was, make sure that you change the default to the operating system that you want to keep. To do that, select the Windows operating system that you want to continue using and then press "Set as default."
Then, choose the Windows version you want removed, press Delete and then click/tap Apply or OK.
To test if everything is OK with the version of Windows that you want to keep, restart the computer and see if you can boot it without problems. You should be able to.
If something terribly wrong happens and you cannot boot correctly, you can repair the boot entries using the Windows installation media. We have an excellent tutorial sharing the system recovery tools you can use, here: An overview of system recovery options for Windows 7. Another useful guide is this one: Fix problems that keep Windows from loading, with Startup Repair.
Step 3. Erase or format the partition used by the Windows version that you want removed
Next, you should format or delete the partition where the Windows version that you want removed was installed. Format it if you plan to reuse that partition to install another operating system, or eliminate the entire volume if you would rather use that space to extend other partitions.
For both these actions, you can use the Disk Management tool in Windows. We have a complete guide on how to use it, here: How to manage partitions with the Disk Management tool, in Windows.
If you do not have the time to read that guide too, just go ahead and open the Disk Management tool. A quick way to do it is to click/tap on its shortcut from the WinX menu (available in Windows 10 and Windows 8.1). Press the Windows + X keys on your keyboard, and then click tap on Disk Management.
In the Disk Management window, right-click or tap and hold on the partition that you want removed (the one with the operating system you uninstall), and select "Delete Volume" to erase it. Then, the available space can be added to other partitions.
If you want to reuse the same partition for another operating system, you should format the partition instead of deleting it. For example, if you want to remove Windows 7 so that you can install Windows 8.1, select the partition, right-click or tap and hold on it, and then click/tap on Format in the contextual menu.
If you want, change the label and the file system. If not, leave the default values as they are, and then click or tap OK.
Windows warns you that you are about to erase all the data stored on that partition. If you backed up everything that was important to you, press OK to continue.
You might also get a warning that the selected partition is in use. To force the format, press Yes and the formatting is done in a few seconds.
Now the version of Windows you wanted to uninstall is completely removed. Note that you can use any partition management tool to do these things. We showcased the Disk Management because you can find it in Windows and use it right away.
What if you have a non-Microsoft operating system installed?
If you have a multi-boot setup that includes non-Microsoft operating systems, like Ubuntu Linux, the steps are the same. The only difference is that you need to use a different tool to remove the boot entry for the version of Windows you want removed so that the entries for the non-Microsoft operating systems are not negatively impacted. One such tool that works well is EasyBCD.
How to remove Windows when only one version is installed
If you installed just one Windows operating system, then the uninstallation is simple. Take the installation CD/DVD or USB memory stick with the operating system that you want to use next and boot from it. Then, during the installation procedure, select the existing Windows partition and format or delete it.
This way, you can reuse that partition (or available space) as you see fit and install the new operating system on it. However, before you do this, remember to backup all your data.
As you can see from this guide, uninstalling Windows is easier than it seems. Anyone can do it with a bit of attention to the steps detailed above. If you are looking for other guides on installing different versions of Windows, do not hesitate to read the recommendations below and, if you have something to add to our guide, write us a comment.