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Add a Hard Disk without changing Existing Drive Letters

The Problem:

Adding another hard disk causes the drive letter(s) to change when more than one drive letter already exists (C: and D:, perhaps more). The 2nd drive becomes D:, and the original D: becomes E:. This may prevent some installed programs from running, or a Windows may no longer boot in a dual-boot setup.

The Solution

Do not create any Primary on the new hard disk.

Create only an Extended partition on the new hard disk, and then create Logical drive(s) in the Extended partition. The Extended partition is really a Primary but is never allocated a drive letter.

The new Logical drive(s) will be allocated the next available drive letter(s) that come after the existing hard disk drive letters. The original configuration will be maintained. A current D: drive will still be D:. However, the CD/DVD drive letter(s) WILL be changed and come after the new hard disk letter(s).

Notes:

These instruction assume Win9x but it's similar for XP/2000/NT.
The same technique applies if adding a 3rd hard disk.
Existing drive(s) on new hard disk must be removed before creating a Extended partition.
A maximum drive size may apply if the drive is to contain a Windows installation.

Warning:

Any data on the 'new' hard disk will be lost when you fdisk it.

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STEP-BY-STEP PROCEDURE:

-----------------------------------

1.1 If dual-booted, boot to the Windows installed on C: and then shutdown the PC.
1.2 Connect the new hard disk, making sure the jumpers and cabling are correct for the role of the new hard disk (master or slave).
      If your computer cannot detect the new drive, you may need to add the line LASTDRIVE=Z
      to your Config.sys file, and/or check your BIOS/CMOS settings.
1.3 Bootup to Windows.
1.4 If it's a new unformatted hard disk, skip to 2.1
1.5 In Explorer, right-click the new hard disk
      (it will be D: if it's the 2nd hard disk - verify this by its contents).
      Select Properties.
      In the Label box, enter DSK2_1
      (to simplify identification, and confirmation, later)
      Click Apply, and then OK.
      If the 'new' hard disk contains more than one drive,
      you can also label the others (DSK2_2, DSK2_3, etc).

2.1 Click Start, point to Run, and then type
      COMMAND
2.2 Type in, and then press [Enter]
      FDISK
2.3 You may be asked "Do you wish to enable large disk support?".
      Enter Y if your system uses FAT32.
      Enter N if your system uses FAT16, often called FAT.
      You are now at the main FDISK Options screen.
      ----------------------------------------------------------------


            FDISK Options

      Current fixed disk drive: 1

      Choose one of the following:

      1. Create DOS partition or Logical DOS Drive
      2. Set active partition
      3. Delete partition or Logical DOS Drive
      4. Display partition information
      5. Change current fixed disk drive

      Enter choice: [1]

      Press Esc to exit FDISK

      ----------------------------------------------------------------

      That "Current fixed disk drive: 1" must be changed.

3.1 Enter 5 to "Change current fixed disk drive".
3.2 Enter 2 in "Enter Fixed Disk Drive Number (1-2)"
      (or enter 3 if the new hard disk is the third hard disk).
3.3 You are now back at the main Fdisk Options screen.

      MAKE SURE IT SAYS 2 in "Current fixed disk drive: 2"
      (or 3 if 'new' disk is a third hard disk)

4.1 Skip to 6.1 if its a new hard disk with no existing partitions.

5.1 Enter 3 for "Delete partition or Logical DOS Drive".
5.2 Delete in this order, skipping whatever does not exist:
      [3] Delete Logical DOS Drive(s) in the Extended DOS Partition
            - enter the drive letter
            - enter the Volume Label (if none, just press Enter)
            - enter Y for "Are you sure"
            - enter 3 for "Delete partition or Logical DOS Drive" (main Options).
      [2] Delete Extended DOS Partition
            - enter Y for "Do you wish to continue (Y/N)..."
            - press ESC
      [1] Delete Primary DOS Partition
      All drives/partitions on this hard disk must be deleted.
5.3 When it's done, you'll go back to the main FDISK Options screen.
5.4 Press ESC to exit Fdisk. Type EXIT to quit the DOS Box.
5.5 Reboot to let the changes take effect.
5.6 Enter Fdisk again
5.7 Enter 5 to "Change current fixed disk drive".
5.8 Enter 2 in "Enter Fixed Disk Drive Number (1-2)"
      (or enter 3 if the new hard disk is the third hard disk).
5.9 You are now back at the main Fdisk Options screen.

      MAKE SURE IT SAYS 2 in "Current fixed disk drive: 2"
      (or 3 if 'new' disk is a third hard disk)

6.1 Enter 1 to "Create DOS partition or Logical DOS Drive".
6.2 Enter 2 to "Create Extended DOS Partition".
6.3 Accept the maximum space that is available.
      Press Enter.
      Press ESC.

7.1 You're at "Create Logical DOS Drive(s) in the Extended DOS Partition".
      It says "No logical drives defined".
      You can create a single Logical drive (accept the maximum offered)
      or multiple drives of different sizes (enter a Megabyte number).
      You must create at least one drive but can leave some space unallocated.
      All drives created will have drive letters below the current letters.
      When all space is allocated you will see:
      "All available space in the Extended DOS Partition is assigned to local drives".
      When finished, press ESC to get back to the main FDISK Options screen.

8.1 Press ESC to exit Fdisk.
8.2 Type EXIT to exit DOS Box.
8.3 Reboot (essential).

9.1 Format the new drive(s).

You can now remove any drive label(s) if you wish. A label is not used internally by Windows, and is used here for easy identification and hence for additional safety.


If you previously had
C: (HD1, Primary)
D: (HD1, Logical)
E: (CD/DVD drive),

you will now have: (where HD2 is the added hard disk)
C: (HD1, Primary) - no change
D: (HD1, Logical) - no change
E: (HD2, Logical) - new
F: (CD/DVD drive) - changed drive letter (it was E:)

or perhaps something like
C: (HD1, Primary) - no change
D: (HD1, Logical) - no change
E: (HD2, Logical) - new
F: (HD2, Logical) - new
G: (HD2, Logical) - new
H: (CD/DVD drive) - changed drive letter (it was E:)

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Please remember that you alone are responsible for the consequences of any changes you make to your computer hardware or software.

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