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Windows 7: Mysterious Drive Letter Change

21 Sep 2010   #1
RP McIntosh

Windows 7 Ultimate 64
 
 
Mysterious Drive Letter Change

I have a non-serious, but puzzling situation. I have an external USB Iomega hard drive. I have it set to be Drive Y. It works just fine. But every once in a while, its drive letter changes. The first time this happened, I thought that the drive wasn't working, because I tried to copy something to drive Y, and found I had no drive Y, even though the power light on the drive was lit, and the drive appeared to be functioning. The only tell tale hint I had was that right after Windows finished booting, I got what I'll call an "error beep"--the sound that Windows makes when you try to do something you aren't allowed to do. Rebooting did not, however, bring the Y drive back. However, what DID happen was that after Windows had booted, I got a dialog box that asked me what I wanted to do with the Iomega drive J--the kind of box you get when you insert media into a removable media drive. That gave me the clue that the drive was working, it had just been assigned a different drive letter (J was the first unassigned drive letter on my system). I went to Disk Management, changed the drive letter back to Y, and all was well.

Since then, this has happened about 3 or 4 more times. Each time, I can use the Disk Management feature to reset the drive letter, and it is then fine for several days or weeks. Does anyone have a clue what could be causing this behavior?


My System SpecsSystem Spec
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22 Sep 2010   #2
Brink
Microsoft MVP

64-bit Windows 10 Pro
 
 

Hello RP McIntosh,

The next time this happens, you might see if using OPTION TWO in the tutorial below instead to change the drive letter may be able to allow the drive to always keep the Y drive letter.

http://www.sevenforums.com/tutorials...ndows-7-a.html

Hope this helps,
Shawn
My System SpecsSystem Spec
22 Sep 2010   #3
RP McIntosh

Windows 7 Ultimate 64
 
 

Quote   Quote: Originally Posted by Brink View Post
Hello RP McIntosh,

The next time this happens, you might see if using OPTION TWO in the tutorial below instead to change the drive letter may be able to allow the drive to always keep the Y drive letter.

http://www.sevenforums.com/tutorials...ndows-7-a.html

Hope this helps,
Shawn
Shawn--

Thanks. If it happens again, I'll give the Registry Edit a try.
My System SpecsSystem Spec
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22 Sep 2010   #4
Brink
Microsoft MVP

64-bit Windows 10 Pro
 
 

Ok. Please let us know how it went.
My System SpecsSystem Spec
22 Sep 2010   #5
RP McIntosh

Windows 7 Ultimate 64
 
 

Quote   Quote: Originally Posted by Brink View Post
Ok. Please let us know how it went.
Shawn--

Will do. Do you have any insight into what causes this behavior to begin with?
My System SpecsSystem Spec
23 Sep 2010   #6
Brink
Microsoft MVP

64-bit Windows 10 Pro
 
 

Anytime an external drive is disconnected and reconnected, there's a chance that it's drive letter may get changed. Hopefully it will stick with the REG setting.
My System SpecsSystem Spec
23 Sep 2010   #7
RP McIntosh

Windows 7 Ultimate 64
 
 

Quote   Quote: Originally Posted by Brink View Post
Anytime an external drive is disconnected and reconnected, there's a chance that it's drive letter may get changed. Hopefully it will stick with the REG setting.
Well, it did it again, and I tried your solution, but I must have done something wrong. I opened Regedit, found the J drive in the listing, right clicked it and chose RENAME, and renmed it from \DosDevices\J: to \DosDevices\Y: and pressed enter. I got a popup box with the binary data in it (sets of hexadecimal numbers, such as those that appear under the DATA column in Regedit). I didn't change anything there, just clicked OK. It did change the name of the entry in the Registry, but the drive remained in Windows Explorer and in the Disk Management application is drive J. So I changed it again in Disk Management back to Y, and so far, it is fine. What did I do wrong?
My System SpecsSystem Spec
23 Sep 2010   #8
Brink
Microsoft MVP

64-bit Windows 10 Pro
 
 

RP,

It sounds like you may have double clicked on the \DosDevices\Y: name to modify it by mistake. That would have opened that pop-up you saw.

Did you log off and log on, or restart the computer to apply the changes afterwards to change in Computer and Disk Management?
My System SpecsSystem Spec
23 Sep 2010   #9
RP McIntosh

Windows 7 Ultimate 64
 
 

Quote   Quote: Originally Posted by Brink View Post
RP,

It sounds like you may have double clicked on the \DosDevices\Y: name to modify it by mistake. That would have opened that pop-up you saw.

Did you log off and log on, or restart the computer to apply the changes afterwards to change in Computer and Disk Management?
You may be right. The first time I did it, I simply right clicked the enter, and chose RENAME. Then when I had changed it, I clicked off it to remove the highlight. At that time, I did NOT reboot. However, the entry in Regedit had changed--at least the title had changed--don't think that the data had changed, though can't be sure. In any case I then went to check to see if the drive was still listed as Drive J. It was. So I went back to regedit, highlighted the \DosDrives/Y: entry, then pressed ENTER. That's when the data box popped up. I did not change anything in the data box. However, the drive at this point remained as drive J. At that point, I went to Disk Management, and changed it to Y there.

When it happens next time, let me make sure I have the procedure right. I should go to the entry in Regedit, right click it and choose RENAME, then change it to \DosDrives/Y: then press ENTER, then close Regedit, then reboot, right? And if I have done it right, it should show up after reboot as Drive Y, correct?

Thanks for your patience.
My System SpecsSystem Spec
24 Sep 2010   #10
Brink
Microsoft MVP

64-bit Windows 10 Pro
 
 

It's no trouble at all RP. Yes, that would be the correct procedure.
My System SpecsSystem Spec
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 Mysterious Drive Letter Change




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