Typically, DiskPart only permits you to delete known data partitions. Note that you still cannot delete the system partition, boot partition, or any partition that contains the active paging file or crash dump (memory dump) filed. Delete and Remove Protected/Hidden EISA, OEM, Recovery, EFI….
https://techjourney.net/diskpart-cannot-delete-a-protected-partition/
1 Can't delete D: Drive Partition in order to enlarge C: Drive Forum. 2  SolvedI'm trying to delete a large amount of video from an external hard drive on my Mac, but no matter what I do, I can't delete it Forum.  Trying to delete hard drive partition and got a error Forum.
http://www.tomshardware.com/answers/id-1917370/delete-partition-hard-drive.html
Delete Volume on USB Flash Drive with MiniTool Partition Wizard. MiniTool Partition Wizard is a free Windows partitioning program with friendly user interface. In this interface all partitions and disks are shown clearly. Please select the partition we want to delete and choose “Delete Partition” from the left pane. At this time, please click “Apply” button to perform the change. After application is completed, our work is done. Now users would know how to delete volumes on USB flash drive when Disk Management can’t do it.
https://www.partitionwizard.com/partitionmagic/can't-delete-volume-on-usb-flash-drive.html
Why Can’t Delete Volume on USB Flash Drive and How to Fix the Issue. Contents: Question: I have a USB flash drive with 1 partition on it, and now I want to make the device back to unallocated space via deleting the partition. Nevertheless, I can’t delete a volume on USB flash drive in Disk Management since the “Delete Volume” button is grayed out.
https://www.partitionwizard.com/partitionmagic/can't-delete-volume-on-usb-flash-drive.html
You cannot delete the system partition, boot partition, or any partition that contains the active paging file or crash dump information. A partition must be selected for this operation to succeed. Use the select partition command to select a partition and shift the focus to it.
https://technet.microsoft.com/en-us/library/cc730824(v=ws.11).aspx
Deleting a partition on a dynamic disk can delete all dynamic volumes on the disk, thus destroying any data and leaving the disk in a corrupt state. To delete a dynamic volume, always use the delete volume command instead. Partitions can be deleted from dynamic disks, but they should not be created. For example, it is possible to delete an unrecognized GUID Partition Table (GPT) partition on a dynamic GPT disk.
https://technet.microsoft.com/en-us/library/cc730824(v=ws.11).aspx
1 delete OEM partition of hard drive SATA Forum. 2  Can't delete D: Drive Partition in order to enlarge C: Drive Forum. 3  SolvedI'm trying to delete a large amount of video from an external hard drive on my Mac, but no matter what I do, I can't delete it Forum.  Trying to delete hard drive partition and got a error Forum.
http://www.tomshardware.com/answers/id-1917370/delete-partition-hard-drive.html
It is currently partitioned in half. I am trying to delete the partition but the option is grayed out when I go into Disk Management. I deleted the contents of the partition, it still says that there is 50 GB being used. I can't see anything in the drive though. I checked Restore Points and the Recycle Bin.
http://www.tomshardware.com/answers/id-1917370/delete-partition-hard-drive.html
DiskPart Cannot Delete a Protected Partition. When attempting to delete a partition or volume with “DELETE PARTITION” command in DiskPart, primarily to remove hidden or system protected partitions, the deletion operation failed with the following error message: Virtual Disk Service error: Cannot delete a protected partition without the force protected parameter set. If you attempt to use “DELETE VOLUME” command to remove the partition instead, the DiskPart may simply crash. To successfully delete any partitions, use the following command instead:
https://techjourney.net/diskpart-cannot-delete-a-protected-partition/
1 delete OEM partition of hard drive SATA Forum. 2  Can't delete D: Drive Partition in order to enlarge C: Drive Forum.  SolvedI'm trying to delete a large amount of video from an external hard drive on my Mac, but no matter what I do, I can't delete it Forum.
http://www.tomshardware.com/answers/id-1917370/delete-partition-hard-drive.html
cannot delete partition
You cannot delete a partition because it contains the active paging file or crash dump information.