Uninstall Windows 7 or Windows 8.1 from a Windows 10 dual boot computer By: J W Stuart September 1st, 2016
You have upgraded or performed a clean install of Windows 10 and afterwards installed Windows 7 or 8.1. Later you decide that you no longer need Windows 7 or 8.1. Here is how you can uninstall Windows 7 (or 8.1) and still keep Windows 10.
It is recommended that you make an Image Backup before you make any changes. Should anything go wrong you can always restore the image and try again. Also manually back up / copy any data files and other documents you want to keep to a USB Thumb /Flash drive. More on this at the end of the article.
1) Start Windows 10 and in the search box type: msconfig and tap the 'Enter' key. Then click on the 'Boot' tab.
2) Select / Highlight the Windows 7 or 8.1 entry and click on the 'Delete' button.
3) Click on the 'Apply' button.
4) Click 'OK' to save your changes. Windows 10 will now be the default and only version of Windows that boots and loads.
5) Click either option.
6) After you reboot Windows 10 open Disk Management and delete or format the Windows 7 / 8.1 partition. You can choose to use the partition for whatever purpose you like or delete it and reclaim / merge the space into your existing Windows 10 partition by using the 'Extend' partition option.
How to remove the Windows 7 / 8.1 partition ----->