Many curious users, having one operating system on board their stationary computer or laptop, often conduct experiments by installing the second, for example, to compare it with the existing one or see how much better or worse it will work. Typically, the same type of OS (for example, Windows) cannot be installed in one system partition, therefore, even during installation, the second OS is placed on a logical drive. When the time comes, and one of the existing systems (old or new) becomes unnecessary, many begin to ask questions about how to remove unnecessary operating systems from the computer without damaging the one that needs to be left to work. The simple deletion of files and directories in one of the sections, alas, does not lead to anything good, and often can even provoke the appearance of situations when the required system completely stops loading. The following is a brief instruction, compliance with which will allow not only to get rid of an unnecessary OS completely and completely, but also to fix possible errors and crashes.
How to remove an operating system from a computer: introduction
So, for starters, let's dwell on some important points, the knowledge of which in the future will determine the correctness of all the actions performed. When you try to delete any of the known operating systems (we consider Windows as an example), it should be clearly understood that it not only saves its own files and folders on the hard drive or in the logical partition, but also creates its own boot components used for a correct start, which usually hidden from the user's eyes. In the same way, special sections are reserved for storing backups in case of unforeseen failures. They are not visible to the user either.
Thus, if you have an urgent problem related to how to remove the operating system from the computer completely, you will have to tinker with all installed components and with all available partitions.
You can also offer several options for removal. How convenient they are, everyone decides for himself.
Uninstalling the OS when installing a new version
As the very first and easiest method to remove an unnecessary OS, you can offer a method that is familiar to everyone and everyone. It consists in simply installing another modification (updated or outdated) on top of the existing system, using the installation distribution, on the basis of which bootable media is created.
Speaking about how to remove 1 operating system from a computer, we can advise you simply to follow the instructions of the installer, and at one of the stages, when you are prompted to select the partition to install, indicate the one in which the unnecessary OS is located and install it exactly there, as it were old one.
If errors are reported, first you will need to delete all available partitions, including those reserved by the system, and after the appearance of the unallocated area, perform formatting. If necessary, at the same stage, you can create additional virtual partitions.
Checking the Windows system directory
Now let's move on to the main topic and see how to remove an unnecessary operating system from a computer if there are two or more of them. The first step is to boot into the OS that is supposed to be left to work.
After that, in the "Run" console (Win + R) , the combination % windir% should be registered , after which the root system directories will open in the "Explorer". The one that corresponds to the currently running system cannot be deleted! If the main OS is located on drive "C", the path to it will be shown in the form c: \ Windows.
Pre-disable OS selection at PC startup
Now you need to disable the use of the bootloader for the system that you are supposed to get rid of.
To do this, by entering the msconfig command, enter the system configuration, go to the boot tab, select the OS that you want to deactivate and click the delete button.
Note: the main OS in which you are currently working will be shown first in the list of systems available for starting. It must not be deleted!
System partition activation
In resolving issues related to how to remove an operating system from a computer that is no longer needed on it, you are already halfway to completion. Since for each of the installed systems, the corresponding section at boot should be active, you must make the appropriate adjustments using the disk management tools (diskmgmt.msc) for this .
Here, when viewing a disk map, you need to make sure that the deleted partition is not active.
Use RMB on the partition with the system that you want to leave, and select the activation item ("Make the partition active"). Such actions are usually applied when the second OS is installed in the logical partition, and the OS is removed from the main system partition on the C drive.
Deleting a partition with an unnecessary OS
Finally, deactivation of all components of the unnecessary OS is completed.
Now you just have to select the partition with the old system in the disk map, and then through RMB select the point of its removal, agreeing with all the warnings that will be issued. Upon completion of all operations, perform a full restart of the computer. In theory, the window for choosing a system to boot does not appear, and the remaining OS boots in normal mode.
Note: if there were more than two installed systems, you will need to delete all partitions in which they were installed initially.
Removing the old OS remaining after the upgrade
Now let's see how to remove the operating system recognized as the old (or second) one from the computer after the upgrade. This can best be illustrated by the example of Windows 10, for which all kinds of updates are constantly installed, and the components of the previous version are stored in a special Windows.old directory . In this modification, you can use the standard rollback to the previous version, and the tools for performing the necessary operations can be found in the update and security section through the options menu.
But you need to delete its files and folders.
To do this, you can simply open the properties of the system disk through the PCM menu, press the cleanup button, and then additionally use the removal of system files.
By and large, you can also get rid of the specified folder manually.
Just before that, it will be necessary for her to change the owner, which can be done in the directory properties, taking into account all the subdirectories, and then set the full set of rights for herself, including changing and deleting. But for security reasons, it is better to use the first technique.
How to remove 2 operating systems from a computer in the main working OS?
In principle, if you initially booted into the operating system that is supposed to be used as the main one, after disabling the choice of your preferred OS at startup and activating the left boot partition, as described above, you can do even easier. How to remove an operating system from a computer that is no longer needed to work, I think many have already figured out.
To do this, in a running OS, you just need to format the partition with the old OS using the most common “Explorer”, but it is better to give preference to full formatting, rather than quickly clearing the table of contents. This method is good because at the end of the procedure you do not have to create a new partition again using the “Create Simple Volume Wizard” for this, followed by the choice of size, letter assignment and formatting.
What if the remaining OS does not boot?
In the end, let's assume that the remaining OS for some reason does not start (even with safe boot). You can fix such problems when starting from bootable media, in which, after selecting the language and region, the system recovery is selected, and then the start recovery item is used.
If this method does not work, use the command line call followed by the Bootrec.exe toolkit, when additional attributes shown in the image above are added after the main command to restore or overwrite the bootloader.
Note: absolutely all of the actions described above, in a running OS, must be performed EXCLUSIVELY with administrator rights when logging into the corresponding account, if there are several, or confirm the execution of some actions on behalf of the super administrator if the built-in account is not disabled.