Windows 10: How do you reset a USB flash drive back to factory settings?

Yeah I see what you mean Bree. Like you say its better for it to have the MBR set up on it anyway so it can be managed in disk management

 

It's easily done (sometimes unintentionally with Rufus). That takes us full-circle to sportsfan148's initial problem that started the interest in 'cleaning' USBs. I used MiniTool Partition Wizard to convert a USB to gpt for this test...

USB flash drive --assign drive letter back to dynamic from static

 

I know it will assign a drive letter to the USB flash drive but does the Assign command fix that drive letter permanently on that particular drive...or will Windows assign a different (dynamic) drive letter to that drive as and when required even though I had used the Assign command on it when I reset the drive with Diskpart? To put it another way when you use the Assign command on its own without selecting a letter with it (assign letter=Z for example)...does that set the flash drive up to have a different dynamic drive letter assigned to it, if required, each time it is plugged into the laptop?

 

Assign command does not assign a different (dynamic) drive letter each time you have connect same storage drive.

 

How do I make it so that the USB flash drive has a drive letter assigned to it dynamically when its plugged in then...exactly the same as it is when you purchase a new USB flash drive? When you purchase a new flash drive..the drive letter is dynamic not fixed. That's all I'm trying to achieve

 

Sorry i have no idea how to do that maybe what you are asking can be achieve by not assigning a drive letter when you format USB flash drive.

 

You are quite right of course. If you wanted it exactly the same you'd have to restore it but who would back up an empty USB drive?

In fact the second partition type (0xC) in your example is correct for USB stick. The first one (0xB) is for CHS (old style HDD). MS got it right and Lexar got it wrong if you want to be pedantic about it (and if you trust Wikipedia). Mind you I manually assign partition types a lot (I have to use hybrid GPT/MBR partition scheme) and always give the 0x7 irrespective if they are FAT or NTFS and that works too so it probably doesn't matter.

Delete its record from the registry.

First assign it some letter like Z so you know what it is. Doesn't matter how - through Disk Management or diskpart assign letter=z - the result is the same.

Then unplug it. Then go to regedit and delete HKLM\SYSTEM\MountedDevices value \DosDevices\Z:

Next time you plug it in it will assign E or whatever is the first unallocated letter.

It is nothing to do with the USB - only your Windows install.

 

To be honest I don't want to mess around with the registry. I think I must be be misinterpreting what the Assign command does? So is it better to not type the Assign command into Diskpart at all. I'm just trying to make sure the flash drive gets assigned a drive letter in exactly the same way as it would do if it was a brand new flash drive being plugged into my laptop. Like I said at the beginning when I first posted I just want the flash drive to be set up and behaving in exactly the same way as when I first purchased it. I thought that if you typed in the assign command (without a letter) it ensured that the flash drives letter would be assigned dynamically from then on i.e if the drive letter previously had a fixed drive letter the Assign command would remove that fixed letter and set it to dynamic. I'm worried that if the drive letter gets fixed by the Assign command that there may be conflicts when other flash drives are plugged in. That's why I don't want to have a fixed drive letter on any of my flash drives..thats why I keep mentioning that I would like dynamic drive letter assignment. Am I getting crossed wires and misunderstanding the way flash drive letter assignment works in Windows?

 

No - assign assigns a letter and stores it in the registry key above (not on the USB). It does the same as doing it in Disk Management except you can assign mount points (letters) to otherwise unavailable partitions.

You could try remove instead of assign. You may find remove just stores it without a mount point and assigns no letter when you plug it in the next time though (which would mean until you assigned a letter you would not see it in File Explorer).

If you don't want to delete the registry key then you'd have to change the serial number (which it matches to the binary value in the registry). I've no idea how to do that - whether it is randomly generated when you format or fixed for the device I just don't know and don't have a blank USB to test it.

 

Remove doesn't sound right then. What happens if two flash drives are plugged in at the same time then that the Diskpart Assign command had given the same letter to?

 

If you assigned separately 2 USB sticks the letter S you mean?

Normally you will not see the second one you plug in in File Explorer and you'll have to manually assign a different letter to it.

Again though this is a function of your Windows install not the USB stick(s). If you tried another PC or reinstalled Windows neither would be assigned S.

 

Yeah..its as I thought then. I'm just trying to avoid conflicts. If I'm understanding you correctly..Is a flash drive assigned a drive letter the first time its inserted into a PC and that letter will stick with that flash drive permanently? In my case then if I'm inserting each of my several flash drives separately (my next available drive letter is always E: after my c: system drive and D: DVDRW drive). Does each of them when inserted individually get drive E: or is the first one assigned E: (stored in the registry)and even after you've removed it ...each one when plugged in separately after that has an individual letter further down the alphabet? Is it the Assign command that causes this? I'm sure ive inserted USB flash drives before that had a drive letter E: one day and was then recognised as F: on another occasion

 

Hey sportsfan148,
Just an FYI ... DriveCleanup is a command line utility for seeing/cleaning up non present drives from the device tree/registry. Be sure to read the DriveCleanup.txt for info/command line switches

DriveCleanup v1.5 - Drive Tools for Windows

 

Why commandline utility? Make life simple. Put Drive Cleanup into a folder and use it periodically to remove all non-present devices.

Download v 0.8.1 of the drivecleanup.zip from Drive Tools for Windows. ( You can use the latest version v 1.5.0. I started using it from v 0.8.1 and still sticking to it)

Unzip it to a folder, say drivecleanup.

You will have two folders Win32 and x64 each containing DriveCleanup.exe for 32 bit and 64 bit respectively.

Remove all USB storage devices from your system (except your USB Keyboard and mouse - if you have) and reboot.

Right click on the DriveCleanup.exe and run as administrator. (Use theDriveCleanup.exe file appropriate for your bit version of Windows.).

After the clean up act, reboot.

( When you plug in your USB devices after this cleanup these will be installed afresh. What you have done is to remove all non-present devices and drive letters associated with them and start with a clean slate. )

Ed Tittel says http://itknowledgeexchange.techtarge...rage-metadata/