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How do I format and partition my new external hard disk?


I have a new 500GB external USB hard drive and would like to format
and partition it. How do I do that?

Well, to begin with, you may not need to. Most come pre-formatted as
a single partition.

But if it didn’t, or if you don’t like the default setup, changing
it is easy. And of course you’ll want to do this before you load that
disk up with data.

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As I said, most external hard drives come ready to use. Just plug
’em in, let Windows discover it, and *poof* there’s another drive on
your system ready to use.

Most will come pre-configured as a single unlabelled
partition using the FAT32 filesystem.

If that’s what you have, and if that’s what you want, you can stop
reading now, since you’re done. You need do nothing more.

“… most external hard drives come ready to use.”

If you want to change what you have, the tools you need to do so are
already right there in Windows.

Start by right clicking on My Computer and
then clicking on Manage. In the resulting application
window, click on Disk Management in the left hand
pane. You should see something similar to this:

Windows Disk Management Application

At the top you’ll see all the logical disks on your system listed
alphabetically by label by default. Below that you’ll see a graphical
representation of all the physical disk drives known to your system. If
a physical drive has more than one partition those partitions will be
shown together on the single physical drive.

In this example, my drive “E:” is an external USB drive. It happens
to be my backup drive where nightly backups are stored.

Remove the Existing Partition

Let’s assume for a moment that I’m unhappy with the current
configuration of the partitions on my external drive and want to change
it. My first step would be to remove the existing partition.

You need to right click on the drive in the lower pane, and you should see this

Disk Management Menu

Important: the next step will delete everything on
the drive. Everything. Make sure this is what you want
before proceeding.

Click on Delete Partition

The representation of the drive should change from “Healthy” to

Partition The Drive

Right click on the drive again, and the option that was once
Delete Partition” is now “New
“. Click on that to set up your new partition.

You’ll then be asked to select “Primary” or “Extended” partition.
Primary is sufficient unless you plan to put more than 4 partitions on
this hard disk. You’ll then also be asked how much of the space to
allocate for the new partition you’re creating.

Typically, I recommend simply allocating the entire space to a single
partition. You can, if you like, allocate less than the maximum space
to the partition you’re creating now so that you have room for
additional partitions on the same hard disk. Remember that each
partition, once formatted, will appear as its own logical disk
(C:, D:, E: and so on.)

You’ll then be asked about formatting, which I’ll cover below.

Once you’ve formatted the new partition, it’ll appear as “Healthy”,
and any leftover space will continue to display “Unallocated”. You can
then repeat this partitioning process on that unallocated space until
your entire drive has been allocated.

Format Your Drive

Assuming that partitioning has been performed above, or you don’t
want to change the partitioning of your drive, the next thing to change
would be the format of the drive.

Important: formatting a drive will delete
everything on the drive. Everything. Make sure this is
what you want before proceeding.

Right click on the drive that you wish to format, click on the
Format item, press OK on the dire
warning, and you’ll get a dialog similar to this:

Disk Management Format Interface

Let’s look at each of those options:

  • Volume Label – is the name that will appear when
    the logical disk is displayed in Windows Explorer, in File selection
    dialog boxes and in other situations. It’s a convenient way to identify
    disks by name rather than only by letter. The label is an attribute of
    the drive, so particularly on removable drives the label stays the same
    no matter what machine you plug it into, or what drive letter it gets

  • File System – I recommend NTFS unless the drive is
    going to be used by older versions of Windows, or by non-Windows
    systems. There’s debate as to whether NTFS is faster (I think it is),
    but it also supports additional security features like file
    permissions, and can typically make more efficient use of larger

  • Allocation unit size – can be left at

  • Perform a Quick format – for the type of format
    we’re doing here, I actually recommend leaving this unchecked.
    A quick format only writes the bare minimum of information to establish
    the disk’s new configuration. If the disk has been in use for a while,
    that’s fine and is what I typically recommend. However, when going
    through the effort of formatting a new disk I suggest using this
    opportunity to have the format process actually write the entire drive.
    It may take a while.

  • Enable file and folder compression – I have mixed
    feelings about this. The overhead of compressing and decompressing
    files is no longer significant with today’s processor speeds. However, I
    have concerns about data recovery if the disk ever experiences an
    issue. My concerns may not be valid, but ultimately, I never run with
    compression on any of my hard disks, preferring instead to compress the
    individual files as appropriate instead. So many file formats, like
    most audio and video files, are already compressed that the compression
    offered by the file system is often negligible. I leave this

That’s it. Press OK and after a period of time
you’ll have a formatted, ready-to-use disk.

A Word on Disk Partitioning Utilities

As you’ve seen, the process we used above to adjust the existing
partitions on the hard disk involve deleting the entire contents of the
disk, changing the partition structure, and then placing the disk back
into service.

It may not have to be that way.

There are third party utilities such as Partition Magic or Acronis
Disk Director that will allow you to resize partitions without first
erasing the disk. Of course I still recommend a full backup of the disk
you’re about to modify first, but these can be useful utilities.

Here’s why I’m not suggesting them: how often do you really
repartition a disk?

In my mind it’s much more common to do it once, and then leave the
configuration alone. A change is typically so infrequent that the
utilities – however good they are – often aren’t worth the effort.

However, that’s obviously a decision you can make on your own, since
it’s a classic time / money tradeoff.

But particularly for a new disk just being placed into service,
there’s no need for advanced management tools. Once it’s empty, and
while it’s empty, it’s a perfect time to perform any partitioning or
formatting or the like using Windows own built-in tools.

Do this

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74 comments on “How do I format and partition my new external hard disk?”

  1. Try booting with (horrors) the 98SE Emergency Startup Disk and use (gulp) FDISK.

    I realize that DOS is beneath contempt, but it has its uses, even now.

    NTFS is not all it’s cranked up to be. FAT32 works very well and any Microsoft OS can read FAT32, except maybe 3.1.

    Slave drives using FAT32 are transportable between or among other Microsoft PCs with, in my experience, no problems.

  2. I didn’t know about this RSS search. You answer all the “BASIC” questions I have been wanting to get answered all the time.
    AMAZING. Many times I simply BROWSE actually FINDING questions and then feel “hey! I always wanted to know that. I cant believe I still don’t know that after being computer-literate for 12 years.”

    Your Fan,

  3. Thanks a lot.I have tried the above method but delete partition menu is grayed out.I logged in as administrator.Can you suggest any other solution?
    Thanks again for simple yet informative article.

    All I can think of is that you likely cannot delete the system partition while it’s in use. Thus you may have to boot from another media (much like what it takes to reformat the system drive).


  4. Dear Sir,

    I have never seen such a good piece of step-by-step instructions. Being a non IT person I found your above article “to the point and precise”. Excellent methodology employed here. Paticularly what I liked most was there was no ambiguity whatsoever and where ever possible, the instructions are backed by logical reasoning. Thanks a million. Keep the goo work going.

  5. my hard is new i hink it isn’t pre-partitioned so removable disk space didn’t apper in the list of the drivers.what’s your advice??
    thanks in advance.

  6. Must echo Ajit’s comments above. Nice to see this sort of thing explained so well and with such clear english. When I put XP Pro onto a new HDD the other day, it prompted me to create a partition, and I did that, only to now find that most of the hard disk is listed as Unallocated, and I am so far unable to do anything about it. If I try to follow the “wizard” in Disk Manager, it seems to work but then keeps coming up with an error. Must be some way around this….I am sparing you the lengthy details, of course, but hope to use your article to sort out the problem. Thanks again!

  7. I have two new Vista Home premiun systems, a Win98SE system, a Win 95 system, and a 3.11 system. I will keep the question simple and expand it later as needed.

    Can all of these systems access and read/write an external hard disk through a network. I have a D-Link 825-Dir dual band router with WiFi and gigabit cable (4 ports)capabilities?

    I would expect to make a separate partition on that external hard disk for each of the systems backups. Is all of this reasonable?

  8. I bought a hard drive (500g) and a HD enclosure. How do i format this drive from scratch. It shows as Maxtor Grizzle in Device Manager, but does not register when i do manage/ my computer. Only internal drives show.??

  9. Hey! I followed all of the above steps for my LaCie 500G external desktop drive and I continually have the same problem…after being connected for a while, it disconnects and a message appears: usb device not recognized…every single time…it’s turning me nuts…Initially I had not formatted so I threw everything out and formatted it as stated here…no luck..after 5 hours of formatting the thing still disconnects…very frustrating…please help

  10. Had just bought a new external HDD and didnt know how to partition it. Your step-by-step process was fantastic! Never had to think about anything just followed your instructions to the T! Thanks a lot…

  11. Thanks a lot for this really simple guide. this is a very basic and often needed task and even windows help confuses you beautifully.

  12. thanks you soo much … i bought Maxtor 350 external HDD yesterday ..and i forgot to ask the shopkeeper to format it for me …. after searching about it on net i came across your step by step process … thanks ..

  13. Hi Leo
    Thanks trillion times.For Such clear guiding steps.Your instructions are invery simple english but so precise and accurate.with your help i partitioned my 1TB external hard disk.Keep it up.Thank U

  14. Thank you so much! I had just bought my new external hard drive and your well written instructions saved me from heart when I thought I had messed up with the formatting.

  15. Thanks Leo. I have been able to format my 500Gb external HDD which I bought with an enclosure. It happen that the HDD was not preformated and thanks to your guidance I have been able to do it. Many Thanks again.
    Vishal from Mauritius

  16. Please let me know if i can
    1) Partition my External Disk
    2) Make it Bootable
    3) Install Windows & Office Applications
    So that it works as a Virtual PC when connected to any another System, where i am not logged in as administrator.

  17. When I delete the partition it will only give me the option to create new ones in NTFS format.

    I want to create a partition in FAT32 format.

    Can anyone tell me how to do that?

  18. If I want to load OS’s on this from multiple computers (hot-swappable), which partitions should I use and how should I format? My OS’s need NTFS.
    According to the partition options in Windows, I can have with Primary 1 to 3 primary partitions AND only 1 extended partition OR 4 primary partitions. Whereas with extended, I can have MORE than 4 partitions…
    If I use extended, what do I miss out? What does a primary partition have which is missing in an extended partition? What do extended partitions have which primary partitions don’t?

    How can I do a HARD format(clear entire contents(all data) of HDD? I read this is the only way to erase some viruses and want to know how to do this when/if reusing a hard drive for an OS.

    In install mode(XP) from disc which partition type(s) does it use/allow?

  19. A little bit of research and I am still not quite certain:

    “C: [PRIMARY PARTITION]is the only bootable one and is where all the DOS system files reside. Regular files can reside wherever you want them to.”
    .)[PRIMARY PARTITION] added to explain context

    .)Then only on a primary can bootable files and OS’s reside?
    .)I would need a primary partition for EACH OS (unique to each computer) I wish to have, correct?
    .)Within a single extended partition can I have more than one partition… or separate space?(I believe it was termed as a “Logical drive”…)

  20. Leo you rock!
    I thought I had killed my 250GB LaCie external hard drive but with your excellent and easy to follow tutorial I was able to retrieve full use.
    Thanks again,
    John McVey

  21. WinXPh external 500GB USB drive it FAT32. I want to split it into 40% FAT 60% NTSF. Reducing partition size (PM8) offers available values as current=smallest=largest = maximum size 500GB.
    There is no choice. Adjusting NEW value to reduce partition size ends up in screen showing values new equal to current values. The disk is not empty. Size reduction is less than existing data amount (lots of space).
    PM8 works fine with built-in disk.

  22. i followed the steps as listed, but once i selected “delete partition” the entire drive dissapeared. i didn’t get an unallocated or healthy message. now my computer won’t even recognize my external drive. what do i do now?

  23. I have the same problem as Chris from Nov 19th. The disk was formatting and it took some time, while I get out. When I was back notebook was in sleep mode. When I woke it ext HDD disapeared. What should I do. It can’t be seen in Disk Management.

  24. I follow your instructions on how to partition my new external hard drive up to the point of “DELETING PARTITION”. Since that will delete EVERYTHING on the hard drive, what will happen to the 79 MG bytes that the drive is already using? Will they be deleted and will it make the drive inoperable? The drive is brand new and out of the box.

  25. I’ve a Hitachi external 500GB sata hard drive. somehow during surfing compying some data from other sources it got infected and then I thought of formatting it. even formatting was not possible so i tried it thro disk management but now it shows me only 465Gb instead of 500GB. I even tried the zero filling which took about 6-7 hrs but even then whenever i connect it to my laptop it becomes slow. I cannot copy anything on the hard disk now.Pls help!

  26. Thanks for the information. My advice is google it and you will come across many options, choose the best one to format and partition.

  27. Leo
    The remove partition procedure worked GREAT!
    However ; i went too far and removed all the partitions now windows does not see my usb drive at all! wht do we do about that??

  28. I HAVE 250GB EXTER. HDD WHICH IS NOT WORKING WHEN I CONNECT IT TO MY PC, whenever i open it,it just give a mess. ‘do you want to format this’ if i click on no then nothing happen but when i click yes it takes hrs to complete just 5%

  29. I just installed a 500Gb internal SATA hard drive. When I go to partition it, (windows XP) the disk manager only offers a new volume wizard, which allows a simple volume only. This simple volume is not recognized by acronis which I was planning to use to reimage my old 80Gb drive onto the new 500Gb drive. Ideally, I’d like to use the new drive as my boot drive and the old one for backup. The question is, what can I do to make a partition that will be recognized by Acronis True Image?

  30. i got a wd 1tb external hard drive and when i follow your instructions it says delete volume, not delete partition…can i get any help please….

  31. i am holding a 500 GB hard disk but I am unable to delete the volume..please help me my operating system is windows 7…. [link removed]

  32. Hi Leo,
    Thanks a lot for this information about creating Partitions. It helped me to create partitions on my newly purchased External HDD.

    Leo, Ive got a question: Why cant we use Windows Vista or 7 or any OS through External HDD? Is there really any way out?

    Just think, isnt it convenient that we use PCs as Nodes & Just carry our External HDD instead of our Laptops. Connect the E-HDD to what so ever PC & you get your own environment there!!!!!!

    Im maddy or incradible ?
    Your Comments Plzzzzz.

  33. Hi sir i am buy to new external hard disk so i want need to that hard disk partition plz give me answer sir i waiting for reply …………

    Please read the article you just commented on. It answers this question.


  34. Hi Leo, great article.
    I have a 2TB usb hdd, Could i partition it in half, so that i can format half in NTFS to play movies on a samsung TV’s media player (dragged & dropped off my PC),
    & format the other half using the TV’s prefered format for recording live TV (vfat i think)?



  35. Ok, so say I have a 500gb h.d. and I don’t have anywhere to back the data that already exists up to. Is there any way to create a partition without formatting and deleting my data that already exists on the disk?

    There are tools (search for “partition management” tools) but backing up to the same drive is pointless – if the drive dies then it takes both your original and backup copies. I strongly recommend that you get an external USB drive and backup to that.


  36. if i have 500gb xternal hdisk, and i want divide it into 3 partition, how can i determine best space for each partition. do u have any calculation for dividing partition on hard disk.

    “Best”? I’m not sure what would be “best” – that depends on why you’re partitioning it at all. I’d leave it a single large partition myself, but if there’s a reason for partitioning it then it’s that reason that might somehow tell you what’s “best”.


  37. Leo, the guidelines you gave have solved my partitioning problems which Microsoft Tech forum and Seagate (the External HDD manufacturer) could not solve.
    May God richly bless you and your team.

  38. Thank you so much, it really helped me a lot. Just a quick question, I have a 2TB external HDD, my friend suggested that I partition it into smaller drives so if 1 partition gets a virus on it I can just reformat the 1 and not the entire 2TB, do you have similar opinions on the matter?

    There’s some sense to it, but I don’t typically partition anything unless I really have to for some reason. I’d leave it as one big drive. One problem is that a virus can infect your *computer* not just a drive – meaning that the virus could appear on all connected drives and reformatting just one would not necessarily get rid of it. MUCH better to focus on doing all the right steps to prevent getting infected in the first place.


  40. Thanks! This helped me a lot. There’s one more question. If i have two partitions on the external hard drive, can i set up password for one partition only?

    The only way to truly password protect a partition is to encrypt it using a tool like TrueCrypt. And yes, you can do that or not for each partition separately.

  41. The only option I get is to format in NTFS I would like to use my drive with a set top box to record to my set top box requires FAT32.

  42. I have 500GB external hard drive, no partitions are there in that and used 100GB. Is it possible to install windows XP in that with out disturbing the data?

  43. @Aravind
    It’s not a good idea to install Windows to an external disk. Even if you could get it to work you would have no end to problems. But just for the record, if you install Windows on a drive with existing data, the data is not destroyed unless something goes wrong with the installation. So a back-up is always in order.

  44. I got a 2T external HD with single partition. I followed your instruction but after the ‘delete partition ‘ command nothing is showing up. Can’t even show a logo of the HD on my computer window nor in the disk management window. No other options to retrieve the previous partition. What would I do. Please tell.

    Unless I’m missing something it sounds like you simply need to follow the rest of my instructions which involve creating a partition on the now unpartitioned drive. The drive won’t show in Windows as a regular drive letter until you create a partition. The drive should show in the disk management application for you to be able to create that partition.


  45. hi i have tryed to format my external hard drive, when i clicked on the format button i get a message saying i do not have sufficient rights to perform this operation. can you help please

  46. @Sunil
    I’m not sure if an external hard drive will work on your car player, as external hard drives require a power source which it draws form the USB port of a computer. If you can get it to work, FAT32 is the format your mp3 music players can read.
    I’ve never tried this, but it may be possible that using a USB Y cable and plugging the short USB plug into a cigarette lighter USB adapter might work.

  47. i left 70gb of 232 gb hard drive on the first installation of my os but i decided to use that space now its showing not able to create but the its showing the 70gb unallocated space ……. ……. -pls tell me the solution…….my mail id is {email removed}

  48. My tv can’t see my 750giga hard disk…….will it see the hard disk if i partion it error msg the device although it can see my 250 giga hard disk

    Your TV? I have no idea. Depends on the TV and why or how it’s supposed to see hard disks in general. Never plugged a hard disk into a TV before.

  49. for the past 5 weeks I was stuck with Drive F 49.5 GB
    drive G6.6GB each time I tried to reformat , each drive formatted separately, I still had 1 drive 2 partition, your method , saved me time and now I have only drive f with 55.GB THANK YOU

  50. Is it possible for me to partition my drive,and still keep the data on it intact ?I just got a new one,and I’ve backed up all my computer data on it.Now I realize I should have partitioned it!

    Some partition management software will preserve data for some operations, but if you’re creating a new partition I know of no tools that let you say “put this data on the new partition, leave this data on the old partition”.


  51. Thanks, Leo. Your instructions were clear and easy to understand! What a big help…I appreciate your time and expertise!


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