Help! My Computer is Fried!!!

Windows FDISK


Healing a Sick Computer

First: Make sure that you have your parent's permission to do this!!! The FDISK program will erase EVERYTHING on your computer's hard drive! Make sure you save everything that you do not want to loose!!! Another good idea would be to have your parents supervise. Even if you know more about computers than they do, if something goes wrong you can always blame it on them! ha ha ha ;-)

FDISK stands for Fixed Disk, which is exactly what this program does. What I am about to show you will restore a virus infected, corrupted, or otherwise unusable hard drive back to the way it was when you first purchased your computer. You will need your original "Windows Boot Disk" or a back up copy of the disk. It should be labeled "Boot Disk" or "Master Restore Disk" or something like that. It should have been included with your computer when you purchased it.

You will also need your Windows CD that came with your computer. This could be a special Windows installation CD which comes with many major brand computers, or simply the regular Windows installation CD. Major computer manufacturers normally furnish additional programs on their installation CD's. Often, both the boot disk and the installation disk are included together on the same CD. In this case you will only have one CD that does both.

It is also common for manufacturers to put the installation files on a separate area, (or partition), of your hard drive. If this is the case, you will probably not have an installation disk. When you restart your computer you should be prompted to enter the Windows setup by pressing F3 or something like that. If your computer is like this, during FDISK you must be VERY careful not to erase this partition! If you do, you will not have any way to reinstall Windows without buying a new Windows installation disk. Lets get started.

First, Do not insert the CD at this time. Insert the 3.5" floppy boot disk only. If your computer did not come with a boot disk and only has an installation CD, or if your computer has the setup files located on a separate partition of your hard drive, you will need to download WinBoot.

WinBoot is a generic boot disk that I put together especially for this tutorial. This boot disk is for Windows 98 and includes a few extra things not normally included with the standard boot disk. Don't worry about that. It should work fine with any version of Windows. The FDISK program on WinBoot is not the Windows FDISK program that is described in this tutorial. It is actually an improved version that is included with FreeDos and is almost identical. You shouldn't have any trouble following along. Ok back to the tutorial.

Restart, (or Reboot), your computer with the boot disk in the computer's A: drive, (or floppy drive). Hopefully your computer is setup to search for the A: drive before searching for the C: drive. If not, you may have to enter the setup program when your computer first starts up. When you first boot your computer you have the option of entering setup. Go there ONLY if your first attempt bypassed the boot disk and began starting Windows. In setup you should see a screen similar to this one:


Select the "BIOS FEATURES SETUP" and enter it. Next you will see a screen similar to this one:


Where it says "Boot Sequence" make sure the order is: A, C, (and whatever you want for the third item) when booting. The picture above has a SCSI drive selected to be searched third. What this does is tell your computer which drive to look for an operating system on first. If there is no disk in the A: drive, it will look on the C: drive, (or hard drive), next for an operating system like Windows. If Windows isn't working properly, a boot disk inserted in the A: drive is often used to start the computer. After you make the changes in setup your computer should always boot in this order unless changed again. This order should be fine for most computers.

Do NOT change anything else in BIOS! Many of the settings found in BIOS can cause your computer to go haywire if set incorrectly! Only change the boot sequence. Make sure you SAVE your changes then exit the setup program. When you reboot again you should now boot to the A: drive. If you're asked to insert a CD just ignore it. Press the "Esc" key and you should be at the DOS "A:\>" prompt. If for some reason you come to a "C:\>" prompt like the one below, simply type "a:" and hit enter. That should get you to the "A:\>" prompt on the A: drive. Once again, make sure you have your "Boot Disk" inserted in the A: drive. Type "fdisk" as shown below to enter the FDISK program.

Here is a little secret. If the reason you are having to restore your computer is because of a virus, before you enter the FDISK program type "fdisk /mbr" (without the quotes). That should repair your master boot record if it was damaged by the virus.


You should now see a screen similar to the one below. Choose "Y" to enable large disk support.


We're in the FDISK program now! FDISK should have a menu similar to the one shown below:


Choose item 4 to display the partition information. Hopefully you will only have one partition as shown below. If there is more than one partition, you may want to delete those also. Be VERY careful here! Remember earlier when I said your installation files may be located on another partition? If they are, and you do not have a Windows installation CD, you do NOT want to delete that partition! Most manufacturers will name this partition something to help identify it. On a Compaq Presario it might be called "PRESARIO_RP", (RP meaning "Restore Partition"), but it could be anything else just as well. If you are unsure, delete ONLY the C: partition. You may also want to contact your manufacturer before going any further just in case. Normally the installation files wouldn't be included on the C: drive, but anything is possible I guess. It never hurts to be safe.


Press "Esc" to go back to the main menu. Choose item 3 "Delete partition or Logical DOS Drive." You should now see a screen similar to the one below. If you had other partitions besides the Primary DOS partition you wanted to delete, delete those first. If not, go ahead and choose option 1 "Delete Primary DOS Partition."


The next screen should look similar to the one below. Enter the partition number to delete, (most likely 1). Enter the volume label, (displayed under: "Volume Label" on this screen). It's fairly common not to have any volume label so just hit enter if you don't have one. Next choose "Y" to delete the partition. After the partition is deleted return to the main menu again by pressing the "Esc" key.


Choose item 1 "Create DOS partition or Logical DOS Drive" from the main menu. You should come to a screen similar to the one below. Select item 1 "Create Primary DOS Partition."


Next you will come to a screen similar to the one below. Advanced users may want to divide their hard drives into different partitions, but for most people it's fine just to use the entire drive as a single partition. Choose "Y" to make the restore process simpler.


You should now see the screen below. Press "Esc" to exit FDISK, then hold down: "Ctrl", "Alt", "Delete", all three at the same time to restart your computer.


Get back to the "A:\>" prompt like you did earlier. Your boot disk should have the format command on it. If you do not have the format command for some reason, download the WinBoot boot disk and use it to boot and format with. It is always wise to scan files you download off of the Internet. A virus could have infected them after they were uploaded. Now that you have a disk with the DOS "FORMAT" command in the A: drive, we will proceed with the format. Type "format c:" at the "A:\>" prompt as shown below and hit enter. Press "Y" for yes and hit enter.


Your drive should now be reformatting itself. This will take several minutes depending on the size of your hard drive partition. When the format has completed insert your "Windows Installation CD" and leave the "Boot Disk" in your A: drive.

If you only have an installation CD without the boot floppy disk, you will need to remove the boot disk from your A: drive. Reboot your computer and go back to the BIOS setup. Change the boot order so that you will boot from the CD drive first like we did earlier for the A: drive. Choose the C: drive as the second drive to boot from.

If you have the installation files on a separate partition of your hard drive, you will also need to remove the boot disk from your A: drive. You shouldn't need to change anything in the BIOS setup as long as the C: drive was the second one listed in the boot order you selected earlier. You will need to pay close attention to your screen when you reboot your computer to see what key to press in order to enter the Windows setup, (or restore).

Restart your computer again by holding down "Ctrl", "Alt", "Delete" all at the same time. The Windows installation process should now begin on its own, (unless you needed to press a certain key). Consult your computer manufacturer's Windows installation manual if needed. Follow the on screen instructions to install Windows. Below is a picture of the Windows 98 installation screen:


That's all there is to it! I have included a text page that summarizes the FDISK procedure. I would recommend that you print it and save it for future reference. I have also included a cool FDISK help file that allows you to practice going through the entire FDISK process.

If for some reason you have lost the fdisk program on your original "Boot Disk," or if you need the MS DOS "Format" command, I have also included them, although I am not sure if my FDISK will be compatible with your specific version of Windows. If you do not have the FDISK program, I would recommend first trying to contact your computer manufacturer or Microsoft for a replacement "Boot Disk." The replacement is probably available as a free download off of the Internet.

You can also download and use my WinBoot disk as an alternative boot disk. It includes both the FreeDOS FDISK program and the FORMAT command. It should be compatible with any version of Windows. To make a boot disk with my WinBoot program, just insert a blank floppy disk in your A: drive and run the WinBoot file. It creates the boot disk for you automatically. Always make copies of your disks, just in case your dog eats one! :-)

Below are the files I mentioned. (If you experience problems trying to download any of these files with Netscape, try using Internet Explorer.)

~ Related Files ~

FDISK Help File (14 KB)

20 Step Summary File (2 KB)

(Hold Down Shift and Click)

FORMAT DOS Command (49 KB)

(Hold Down Shift and Click)

FDISK Program (63 KB)

WinBoot Boot Disk Creator (991 KB)

~ More Information ~

For more information on FDISK visit
FDISK Information

For Windows support visit
Windows Support

For downloadable boot disks visit
Boot Disks

If you have further questions contact me at

Good Luck!

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