Issue: I wanted to use faulty laptop’s old hard drive as external drive but i when i trying to delete all partition, i were only able to delete drive C, other partitions like Recovery, System and Reserved etc doesn’t have the option to delete.
Using DISKPART command in command prompt
1) Run command prompt as administrator
2) Type diskpart
3) Type list disk
4) Type select disk 1 (disk 1 is the old hard drive)
5) Type list partition ( it displays partitions have not deleted)
6) Type select partition=1 (select the first Recovery partition to delete)
7) Type delete partition override (delete partition)
8) repeat step 6 and 7 to delete rest of the partitions
9) Type exit (to exit DISKPART)
10) Go to Disk Management, old hard drive’s partitions have been deleted.