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To Delete your existing partitions choose option 3 from the Fdisk Main Menu
After Pressing 3 this menu will appear
Delete DOS Partition or Logical DOS Drive
Current fixed disk drive: 1
Choose one of the following:
1. Delete Primary DOS partition
2. Delete Extended DOS Partition
3. Delete Logical DOS Drive(s) in the Extended DOS Partition
4. Delete Non-DOS Partition
** Below you will find an explaination for each menu choice and the order that you must delete them in **
1. Delete Primary DOS partition - Use this option to delete your main primary partition. However if you currently have any Extended / Logical DOS partitions you must delete these partitions before you will be able to delete the Primary DOS partition.
2. Delete Extended DOS partition - If you have your computer partitions into more then one drive, use this option to delete the extended dos partition(s). You must delete the Logical DOS Drive(s) before you can delete the Extended DOS partition.
3. Delete Logical DOS Drive(s) in the Extended DOS Partition - This option would be used first if you have extended DOS partitions and wish to delete the extended partitions.
4. Delete Non-DOS Partition - This option is usually used for partitions that either have been created by third party applications such as a DDO or other operating systems such as IBM Warp, Unix, as well as various other operating systems.