On the disk management page, locate your USB, right-click on it and select mark partition as active. Then right-click on your windows start icon and select disk management. To do that, attach your USB stick to your PC, again ensure you have no files in it, you can choose to format it in case it has some initial configurations. Then using the disk management tool, mark the USB as active.

This process will not downgrade your Windows from any version toit only provides you the command line terminal from the build from where you can run the bootrec commands without errors. So for this second fix, you will need to configure a bootable USB with the build installation files in order to run your bootrec commands without errors. Unfortunately, if you try to use the Media creation tool from Microsoft official download page, you will end up with the latest Windows 10 build on your USB stick. So running the same command using an earlier version like build will not cause this error. There have been several reports that this error is peculiar to the later Windows 10 installation media files, like build and the latest build install media. It should bring you back to the page below. Type exit and hit enter to close the terminal. It should again say the operation completed successfully. It should say the operation completed successfully. Next type V: and hit enter, it should take you to the V volume. Now type exitand hit enter, this should close your diskpart session. It should say diskpart successfully assigned the drive letter. Now you will need to assign another letter to this volume, you can choose any letter you want, but note that some letters are reserves by windows and others like FCED in some cases are already in use so you have to use some other letters. Next run the command, select vol, it should say volume 1 is the selected volume.

This is where you have your EFI directory. It should display all the volumes you have on all the disks attached to your PC. It should say disk 0 is now the selected disk. Next, you want to select the disk where you have your Windows file, normally is the disk 0, so type select disk 0 and hit enter. Wait till you see the diskpart prompt, then type the command, list disk and hit enter, this should display all the disks you have attached to your PC. To do this, on the terminal where you got the access is denied error, type in the command, diskpartand hit enter. But what do you do if bootrec denies you access to some command extensions like the fixboot command?īelow are two possible ways to solve this problem. This is why the bootrec command is quite important. This command is normally used for fixing a number of startup problems you might be having in Windows.

Chkdsk access denied elevated mode