It will complain that it’s already in use, but I can go ahead and delete it because it’s just a copy of Windows. This is actually an old Windows disk that I want to erase, so I can use it as a secondary storage disk.

Note that this isn’t my current Windows boot partition, which is on disk 1. The fifth one actually does give me the ability to delete it, so I’ll go ahead and do that. The second, third, and fourth partitions have only one selection. In fact, as I right-click on the subsequent ones, the option to delete doesn’t even show up. On this first partition, Delete Volume is obviously greyed out. If I right-click on any one of these, you can see what options are available in the context-sensitive menu. The partitions I want to delete are on disk 0, which shows five partitions. Let me slide this over so I can show you in this corner of the desktop.

To start the utility, simply right-click the Windows button and choose Disk Management. The symptom is apparent when you look at a disk in the Disk Management utility of Windows. These partitions can sometimes be labeled as recovery partitions or OEM partitions, but they all have one thing in common: they’re protected, making them impossible to delete from certain tools in Windows. Today, we’re going to delete disk partitions in Windows 10 that appear to be undetectable.

Diskpart delete partitions