How to delete an unintentionally dual booted OS in windows 10?

So I had win7 32 bit on my machine, then I installed the 64 bit version. I don't think the 32 bit install ever got removed, because after I upgraded to 10 it began taking me to the dual boot screen on startup. Now I can't delete the 20gb of windows 7 files off my ssd (it won't let me- says that "trusted installer" won't let me make make changes to these files).

So windows forum, my objective here is to have win10 be the only OS on the machine, and I'd like to have it installed on my ssd ( (D:) in the photo).

Thanks everyone!



Well-Known Member

Heres some steps you could try:

1. msconfig in search bar.
2. Go to boot tab, choose default booting OS.
3. Delete the old OS using disk management.
4. Copy OS to ssd.

Hope this helps.


Well-Known Member
You can also delete the old OS using msconfig, just be careful

You can also delete the old OS using msconfig, just be careful

So how would I go about deleting the old OS with diskmgmt?

Also, what do I need to be careful about if i delete the old OS with msconfig?


Well-Known Member
i would use msconfig, as you can see in the boot tab you can choose whether to delete an OS or not. This would be the way i would do it.


Excellent Member
Microsoft Community Contributor
You need to be careful, the boot files are currently on the HDD. Since the SSD shows as an Active partition, you may have some there also, but removing the HDD would let you know. Setting the SSD as the primary boot device may also help. If it stops booting, reattach the HDD and set it as primary boot device.

But to be clear, according to your attachment, you are using the HDD to boot and the SSD for your OS.


Essential Member
Microsoft Community Contributor

You can also use EasyBCD to make sure that the computer boots directly into Windows 10 without looking for Windows 7.

The free versions at the bottom of the page...


If you delete Windows 7 while it's still in the boot list your computer won't boot, (I found this out the hard way years ago). LOL

Use EasyBCD to set Windows 10 as the default OS, remove Windows 7 from the boot list, and tell it not to show the boot menu,

Once you reboot and get it to boot directly to Windows 10, it's then safe to remove the Windows 7 installation.

Don't format the hard drive or remove the boot sector, if the boot files are on that drive that would screw things up as well.

Just delete the Windows install and related files, i.e the Windows 7, Program Files and Program Files (x86) folders if you are not running any of the software installed in them.


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