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How do I stop Windows from reassigning my external drive letters?

by Lee Koo (ADMIN) CNET staff/forum admin / March 14, 2008 3:05 AM PDT

Greetings! Windows has many annoying "features" that we all
have to put up with. My main complaint is that regularly
Windows decides to make changes to settings, which then have
to be re-set by the user. I'll give two examples. I
regularly connect USB external hard drives and USB flash
memory cards. Using Computer management's Disk Manager, I
will change the drive letter. My Toshiba hard drive is set
to (T:) and the Western Digital to (W:). My flash card is
set to (U:). These all have a desktop icon. I'll also set
the action required when plugged in to open a folder. Then
Windows decides to change the letter and prompts for what to
do, rather than automatically open a folder. Is there a
method to this madness, so that the assigned drive letter
stays assigned? Any detail explanation why this happens and
how I can fix this annoyance is appreciated.

Submitted by: Reg

Snippet from community newsletter (3/21/08):

Reg, I can see your frustration. I know that if you have
desktop icons created for those removable drives, once you
remove them and plug them back in, the desktop shortcuts will
not access those drives again--because Windows naturally
reassigned the drive letters to the next available drive
letter. Unfortunately, many of our members' answers stated
that it?s something you cannot change in Windows--here is a
simple explanation by our member alswilling and another more
detailed answer by member bus. Other members suggested not
unplugging those drives and they will remain assigned to the
drive letters, but that makes the ?removable? in removable
drive pointless. However, I did come across a solution by our
member techtype who suggests a program called, ?USB Drive
Letter Manager? (a note of warning that I have not tried or
tested this software nor am I here to support it, so if you
decide to try this software, purchase and use this software
at your own risk.) However, if it works out please let us
know. If any members have any other solutions to Reg's
question, please let us know about it. The topic is open for
discussion and I look forward to see what you have to offer.
Have a fantastic weekend folks, thanks for all your efforts
in helping one another out.

Answer by alswilling

Answer by bus

Answer by techtype

Please read thread below for more advice from our members. If you have any additional solution for Reg, click the reply link and in detail, post your recommended solution. Thanks!

Message was edited by: admin
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Non-Microsoft drivers are often to blame.
by Nargg / March 14, 2008 12:40 PM PDT

If you've loaded drivers for any of those devices, those drivers can often cause all types of headaches. Remember, Windows is not fully a 100% Microsoft creation on any given machine. There are a LOT of different companies and developers that go into the final product that you are using on your desk. Many drivers, many programs and many "features" that are outside the realm of Microsoft's ability to create a stable system. Hardware itself can also be to blame. Much of today's hardware includes it's own internal "smarts" and small routines to do tasks when they are turned on or plugged in. Those routines can also cause changes to occur that are not intended.

My first recommendation is to never load a driver unless you need to. So many devices already work out of the box without special drivers. Printers are usually the exception, but not always. Flash cards unfortunately are the worst for special drivers that are usually not needed, or are force installed upon the first insert of the card or USB flash stick. Be very wary of such devices that have "special software" included.

Best thing to do is to find the original maker of the machine, or the maker of the hardware that might be causing the problem and ask them if their drivers or hardware could cause such headaches. They may have an updated driver that fixes such problems.

Good luck.

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by puma / March 21, 2008 11:54 AM PDT

fortunately this is not an issue with other operating systems - mwahaHaHA!!!

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You have to boot up with the same stuff every time

I'm not an expert on Windows, but my experience tells me that to avoid this problem you need to boot up with the same configuration each time. After booting you can remove the device and when reattached it will end up with the same drive letter. I know this is an annoying, but life with Windows has much bigger annoyances: life with VISTA sucks.

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reassigned drive letters

Why fight them? Join them, accept their letter designations and see if it will remain stable. After that I dont know, but I sure wouldnt keep beating a dead horse.

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How do I stop Windows from reassigning my drive letters

This goes way back to DOS. MicroSoft expects the drive letters to be consecutive, alphabetically.

So a floppy is always 'A', the first hard drive is always 'C', the second hard drive is expected to be 'D' and the next is the CD drive. If there is no second hard drive then the CD dive is 'D'. and so on and on.
This comes from the early versions of DOS ( before Windows. )
I know. I used to program little programs for DOS to automate the batch language.

I know that Windows XP and later are a little confused on this issue.
I would suggest that you take a hard look at the hardware configuration, with this in mind. If you have to disable something in order to abide by this simple rule in order to get things working like they should, then do it.
Once you understand the underlying roots of the problem, it's a piece of cake.

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Reassignment of drive letters

The solution is, get a Mac. The fact that you have to assign labels to the devices has always been a bother, even back in the days of DOS and CPM. The Mac has never had these issues. With USB and Firewire, you plug something in, it shows up on the desktop, you use it, unmount it when done, and unplug it. You don't have to poke a Mac in the eye to tell it what's hooked up.

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Nope, you're wrong dude
by Etamar L. / March 26, 2008 12:35 AM PDT

Windows does just that, like a Mac. The problem is not there. The issue is that the name of the device will be changed next time, and in Mac the device will be changed AFAIK as well, if you, for example, plug it in a different port than before.

I do not know the real solution, but I guess the right way to solve it is get a utility for maintaining each "volume label" or "disk id" with its own letter. Hey, I might even write one.

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Sorry, pathnames are still a problem.
by TreknologyNet / March 26, 2008 7:23 PM PDT

If you've tried writing any software inside the Mac OS, it's just as bad as DOS and WINDOWS when people insist on putting things inside folders that are nested ridiculously deep.

Considering that the Mac can mount to drive volumes with identical names doesn't help things either.

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Yep great suggestion
by NeoMalfoy / March 27, 2012 7:04 AM PDT

and for those of us that can't afford to drop 1500 bucks on a mac at the drop of a hat....

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Re: Lost settings

If your computer keeps losing its settings, the first thing I would do is check the date and time on the computer. If the computer has lost the correct time and date settings, then the cause of your issues could be a dead battery on your computer's motherboard.

Fortunately, batteries are usually fairly easy to replace. Most motherboards use CR-032 lithium batteries, which can be found in many stores. They have a similar shape as watch batteries.

To replace the battery, you would first have to remove the outside cover from your computer. As cover designs vary, follow the directions from your computer manufacturer on how to do this. If your computer is still covered by a warranty, you may have to take the system to the shop. If you open the computer, your warranty may become void. Check the terms and the conditions before opening your computer.

Once the cover is off, remove the old battery from the socket. You could use a small screwdriver to get the battery out. The new battery can be put into the socket.

After the new battery is installed, put the cover back on your computer, plug in the cables, and power on your machine.

When you first turn on the computer, you may be prompted to accept the computer settings. Follow the on-screen instructions as to which key you should press. If possible, choose to enter setup so that you can change the date and time. Save the settings and exit the CMOS Setup. Boot the computer up.

I hope this helps.

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Use USB Drive Letter Manager (freeware)

USB Drive Letter Manager (USBDLM) is a freeware Windows program that gives users control over Window's drive letter assignment for USB drives.

With it you can define default letters for USB drives and much more. See for more info.


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USB Drive letter manager
by JimBC / April 9, 2008 5:50 AM PDT

To avoid this problem the only real solution is indeed the USB drive letter manager.
It's BTW some kind of service that runs i/t bckground.
Why Windows until now still hasn't fixed this drive letter behaviour is typical of the whole Microsoft attitude.
Why can't it be fixed with some file that the OS is looking for when the drive is attached; that file that would contain the info for the letter to be assigned to is in fact what's needed.
It is what the USB Drive Letter Manager does through a service and a file on the drive.

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well first you could try going into my computer set the name hit apply and then ok. If that doesn't work try going in to control panel and swithching the automatic updates off. IF YOU DO THIS YOU WILL HAVE TO DO THE UPDATES YOURSELF!!! and I can't stress how important it is to update your computer.

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Assign drive letters

Hi! Make several empty folders then assign these with drive letters up to the number you want. Once you have done this windows will happily accept these and will not try to reassign any more.

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Usb Ports

Try plugging them in the same usb ports every time because i think when you use a different port it reinstalls the device for that pot and then you lose your lettering and options.

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Changing letters of drives

How to assign a drive letter
To assign a drive letter to a drive, a partition, or a volume, follow these steps:

1. Log on as Administrator or as a member of the Administrators group.

2. Click Start, click Control Panel, and then click Performance and Maintenance.

Note If you do not see Performance and Maintenance, go to step 3. Performance and Maintenance appears in Control Panel only if you use Category view. If you use Classic view, Performance and Maintenance does not appear.

3. Click Administrative Tools, double-click Computer Management, and then click Disk Management in the left pane.

4. Right-click the drive, the partition, the logical drive, or the volume that you want to assign a drive letter to, and then click Change Drive Letter and Paths.

5. Click Add.

6. Click Assign the following drive letter if it is not already selected, and then either accept the default drive letter or click the drive letter that you want to use.

7. Click OK.

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This is the solution
by sarahg1975 / March 21, 2008 1:55 PM PDT

Read the one above my message labeled "Changing letters of drives". This is the correct solution. Are you paying attention CNET? Using the Computer administrator to change the drive letter to the one you want sets that drive letter in place for the drive. Windows will remember when you unplug the drive and replug it back into the system at anytime. Even if you put the drive in a different external case windows will still remember the drive letter.

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Changing letters of drives
by Tiesenhausen / April 11, 2008 1:00 PM PDT

mcstanley's reply is the solution that works. I set my three identical flash drives this way. Windows XP now always recognizes these drives as P, Q, and R, and knows which one is Library, which one is Photos, and so on. Furthermore, I can now make shortcuts in any folder on my hard drive to open any folder or file on any of the three flash drives. If the flash drive is removed, I just get an error message, but as soon as I plug the flash drive in, all the icons and shortcuts will still be there and still work.

Many thanks. mcstanley's solution seems to have been overlooked when the responses to this problem were summarized. Most of the responses don't even seem to have understood the question.


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Drive Letterring

Unfortunately, each time you connect and disconnect an external drive, Windows will re-assign a letter to it based on the order it is attached. In other words, if you plug in your Toshiba HD first, your WD second and your thumb drive third the Toshiba will be assigned the first available letter, then the WD and finally the thumb drive. If you plug the WD in first it will be given the first available letter assignment.

There are three options:

1) Mount the drives in the same order each time you plug them in. This will maintain the drive letters.
2) Keep the drives plugged in and only remove the one you need at the time.
3) Mount the drives in a folder partition on your hard drive. Below are the instructions on how to do this. Although the English is a bit shaky, it gives you the idea. You can access this at

Hope this helps.
1. Click on Start Menu, then select Run. In Vista, press Win+R key to open Run command.
2. Type DiskMgmt.msc to open Disk Management.
3. Right click on the new hard disk or remaining unallocated space, and then select New Partition or New Simple Volume (in Vista). If the partition has been created, delete the partition and re-create it.

For partition that has been allocated with drive letter and path, right click on the partition and select Change Drive Letter and Paths.

4. In the ?New Simple Volume Wizard? or ?New Partition Wizard?, follow the instructions on screen such as selecting the size of the new partition, until the the Assign Drive Letter or Path screen.
For existing volume/partition, click on Add button to add a new path instead.
5. Select Mount in the following empty NTFS folder radio button, and then select Browse? button.
For existing volume/partition, the ?Mount in the following empty NTFS folder? is automatically selected. Users cannot assign more than one drive letter to a partition, but can assign many paths (folders) to a partition.
6. Select an empty folder that you want to mount this new partition. Click on New Folder to create a new directory if needed. Once selected the mounting folder, click OK button.

7. For existing partition already with drive letter, process is completed and users can now open Windows Explorer to browse the partition content in the mounted folder.
Else, back in the wizard, continue to follow instructions on screen to complete the wizard by selecting file system, allocation unit size, volume label, decide whether to perform quick format or whether to enable file and folder compression. Wait for the disk formatting to complete too. After process completed, a folder is linked to the partition/volume.

As mentioned, users can assigned many folder path to a single volume or partition. Users can also remove the relationship of folder mount point with volume at any time, or change back to a drive letter. Even already mounted on a folder path, a drive letter can still be assigned to the partition too. All these administrative operations can be done on the Disk Management. Best of all, changing drive letter or folder paths of a volume will not delete the data on the drive.

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Use DiskPart...

I have found that the best utility to switch drive letters is DiskPart, which is found in Windows. Other methods will work for a while, but it seems that they all seem to change over time. Since I have shifted to this method, I have never had it change drive letters on me, so it seems more secure, although it is a little tricky to do.

First, click on the Start button, click on "Run...", and type in "cmd" (without the quotes). When the Command Window opens, type in "diskpart". From here, you can type in a question mark like "?" and hit the Enter key and it will show you a list of valid commands. For this exercise, we are going to use "List Volume", "Select", and "Assign".

Now type in "list vol". This shows all of your drives and what drive letters they have. In the last column on the right, the INFO column, you will notice that on one of them, it says SYSTEM. This should be your C:\ drive. That drive should stay as it is, so whatever letter it has, leave it that way. If you change that drive letter, it will screw up Windows so it will not work anymore.

To change the drive letter, it is a two-step process for each drive letter you want to change. Let's say you want to change drive D:\ to drive V:\. Then you would type in "Select volume d" and hit the enter key. Then you need to type in "assign letter v" and hit the enter key. It should give you a message telling you that it is done. Read that message, because sometimes, it may say that you have to re-boot before it can finish the job, or if it is a drive letter that you cannot use, it will tell you so and give you the reason that it cannot be used.

Now, to make sure that it worked, type in "list volume" and hit the Enter key. Check and make sure that your D:\ drive is, in fact, now your V:\ drive.

Do this for each of the drives that you wish to change.

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To fix a problem with your windows based PC

Buy a MAC and you will never have such problems. time is money and with windows they waste time trying to find or fix problems that should never happen. I have been using PC's for almost 30 years and I found with a MAC you have no problems and if one does arise Apple makes sure to render the problem with outstanding support and help with your system. Apple has taken the problems out of using a windows based PC and given us a computer that does what it should with the speed and accuracy that everyone wants. Plus with todays MAC's you can have both windows and MAC based programs on the same system, but over time you will drop the windows programs and find the apple programs out perform windows by lightening speeds. This will give you more time to enjoy day and less time worrying about losing data or fixing some bug that has wasted your time. TRY A MAC AND YOU WILL NEVER GO BACK.

Have a great day
hangtown video

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by rlessmue / March 15, 2008 9:13 AM PDT

Look, I know you are trying to help someone who has a PC problem but the solution you provided is not a logical one...
unless you plan to BUY him a Mac!
Are you?!!!
(It's like telling someone - that because their car is not running right, they should not have bought that car and should have bought a different one!)

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by puma / March 21, 2008 1:09 PM PDT
In reply to: a Mac?

it's about cutting your losses short before it is too late...

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Live with it...

Whenever a removable drive is plugged into the USB port of a machine running Windows, Windows automatically assigns the next available drive letter. Since on most Windows XP machines with a single internal hard drive and one CD or DVD player/recorder installed, C:\ drive is the default assignment of the primary drive containing the operating system and system files, D:\ is the partition containing the recovery files, and E:\ is the CD or DVD player/recorder. Using that scenario, the next available drive designation would be F:\. The letter designation assigned to an external storage device depends on how many internal hard drives and CD/DVD drives one has installed.

As long as the external drives are plugged into the USB port, the drive letters that you specified will remain assigned to those drives. However, when you unplug the drives, Windows does away with those drive letter assignments; because the drives no longer exist on the machine. When an external storage device is plugged in, then Windows does what it was designed to do: it assigns the next available drive designation to the "new" device.

Why not just go with the flow--live with it? If you plug in the same devices in the same order each time, then the drive letter designations will remain the same each time you plug them in.

That is the easiest solution and the short answer.

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by Mr-Opinion / March 21, 2008 1:50 PM PDT
In reply to: Live with it...

Thats the problem, and has been getting worse due to people who 'live with it' MinoMo has been pumping out overgrown junk programing/OS's that force us to jump through hoops to use a simple computer which was supposed to serve us - not become our master
If we'd quit 'living with it' maybee the problem would get fixed

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But there is no problem to be fixed
by DADSGETNDOWN / March 21, 2008 4:56 PM PDT

Do you think it should assign a new drive letter if you RE-connect
the same devices in the same place in the same order ?
That makes no sense.
If it RE-Assigned a drive letter under those conditions,
THAT would be jumping through hoops. to find and realize that the
drive letter had been changed.
It "serves" us perfectly and logically in this manner.
This reply was not thought out, and must have got hung up on the
"why not live with it?" phrase.
Stop being so negative and illogical.
and pump us out a not so overgrown junk programmed OS.

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Boy did we miss each other here ?
by Mr-Opinion / March 21, 2008 5:56 PM PDT


somehow I know we are on the same page, but not reading it the same way

That was my whole point "living with it'" windows arbitrary re-assigning of drive letters is unacceptable, therfore I found the suggestion to which I responded 'unacceptable' - so I am confused about your response

One should once and for all be able to asign specific drive letters to speciffic periferals - period - windows actually keeps track od serial numbers of USB items plugged in at various times - U can look them up - so why can't windows be taught to match drive letters to serial numbers - seems so simple - but MiniMe will never figur it out -they realy don't care what you and I want or need - as long as they can covince us to upgrade... stop buying -- they'll figure it out

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sorry I will waste one more reply
by Mr-Opinion / March 21, 2008 6:10 PM PDT

You feel I missinterpited the statement to which I replied - please read it again - it clearly suggests that the best/easiest solution is to live with it and just plug in all your perifferals in the same sequence in the same ports and than the problem is solved - Illogical - I may not even have enough ports for those periferals and be swapping periferals - so another solution is needed - and that was the Original posts request - living with it was not an option desired.

Re re your request that I re-write a les bloated - more efficient OS - two things - I never claimed to be a master programmer or I would have done so, secondly others have done so and been squshed by MS's marketing machine - and as an additional thought - what to you really and I mean really get for 2.5 Gig of XP-pro that I didn't have with 2.5 meg of win 3.1 - I mean stuff I want - not stuff I'm stuck with even though other 3rd party programs are better - trust me if is was code written is would be 1/10th the size and 10 times faster and that much I do know - a code written c-64 program swapped menues faster than windows does (I wrote one) so would could a code written program do on a 3GHz dual-pent ???? it be fun to find out

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living with it
by haf canadian / March 22, 2008 5:56 AM PDT

I think the point was not just that he loses the assignment when he unplugs a device, but also by default of such action he loses the parameters he set up for accessing it. Therein lies his real beef. To "just live with it" is no simple hassle for him. Plugging the same device back into the same port is okay (though perhaps multiple devices have to be in the same order if Windows assigns by "next available"), but he'll still have to re-instruct Windows about access specifics/preferences each time. I suggest he read the answer by "bus".

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telly correct
by Mr-Opinion / March 22, 2008 3:42 PM PDT
In reply to: living with it

yes the assigning is secomdarry - actually no one would give a hoot if it didn't create program/data finding functions - WICH I CAN'T LIVE WITH

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