1st method of OEM / EISA partition deletion:
But using the command console you can do it without much hassle.For this, first open the DOS command. Start (1) then in search or run type “cmd” (2) and when cmd appears in the menu, right click (3) on it and then run as administrator (4).
Then type diskpart and then enter your keyboard.
Now that you are in the diskpart program, type “rescan” again and then enter your keyboard: The utility will start searching for the disks and partitions of your computer. Remove an oem or eisa partition.
Now we will choose a disk and then the partition to format: Select disk: Type “list disk” then validate with enter the keyboard to display the list of available hard disks on your computer:
Now you will select the disk containing the partition to delete. Type “select disk” then the disk number “and then tap Enter.For example: select disk 1.
delete an oem or eisa partition 5Selection of the partition: Then type “list partition” then Enter to display the available partitions on the selected hard disk.
Select the partition to be deleted by typing “select partition 1” for example to select partition 1. Same as for disk select the number according to the list and partition EISA or OEM to delete, then tap Enter.
Finally type “delete partition override” and type Enter. You can exit the command window, your partition is deleted.
2nd method of OEM / EISA partition deletion:
If the first method is too complicated, then take a windows installation cd, and proceed as if you were going to install the system. Then when the program asks you to select a disk for the installation choose the OEM or EISA partition to be removed. and have it removed. As in the picture below.
Once the partition is removed, remove the cd and reboot the pc. This method is simpler but requires a windows installation cd, or linux.