All OEM computers (laptops and desktops) come with an EISA partition configuration in the hard drive. EISA partition is primarily a FAT or NTFS file system and used for recovery programs installation and diagnostic tools for the computer. The partition size ranges from a few to even 10 gigabytes in some computers depending upon the operating system, programs installed and hard drive storage capacity. The EISA partition can be hidden or visible with an assigned drive letter. The partition can be deleted from the hard drive and freed up for usage as individual partition or as an extension to an existing partition. The deletion can be performed from CMD or from the control panel.
Turn on the computer and log in to Windows through an administrator account.
Press "windows key + r" to open the run application. Type "CMD" and press enter. CMD application will be opened.
Type "diskpart" in the command prompt window and press enter. Disk partition utility program will start.
Type "list disk" in the program window and press enter. The program will display all the disks connected to the computer.
Select the disk by typing "select disk #" where "#" is the number (0, 1, 2 etc.) displayed against the disk as disk 0, disk 1 or disk 2. Upon the selection, the system will display a message "disk # is now the selected disk".
Type "list partition" and press enter to see all the partitions on the selected disk. The EISA partition will also be displayed and can be identified by its size. Make a note of the corresponding number of the EISA partition.
Type "select partition #" for the partition you want to delete. Type the number of the EISA partition in place of "#" in the command line.
Type "delete partition override" and press enter to delete the partition. Accept any warning if displayed by the computer to delete the partition.
Restart the computer, log in to Windows and go to the Control Panel. Open the "administrative tools" option and run the "format and create hard disk partitions" utility program.
Find the deleted partition as "raw partition" in the program window. Select the partition by clicking on it and format the partition as FAT or NTFS. You can also extend the partition to an existing partition by selecting the "extend partition" option.
Make sure to create a backup of the EISA partition on a DVD or a hard drive before deleting it. You might not be able to get this data later from your computer manufacturer. Do not run any other commands in the CMD window without proper guidance or know-how.