Need drive letters to be consistent

RoWin7 · 16 Mar 2019

Both of my computers have Drive C and Drive (partition) D.

I have 3 USB sticks. G: is plugged in permanently to this machine, to back up 3 folders nightly through a small backup program.

As my 2 computer still have networking issues and aren't networked yet, I move the other 2 USB sticks, E and F, back and forth between the 2 machines to transfer or copy data.

I just found out that my 3 folders hadn't been backed up since 1/6 because this computer had changed G: to F: ,confuzzling the backup program. When the 2 temporary sticks aren't plugged in, both computers rearrange the letters.

Is there a way to keep the drive letters stable even if all the sticks aren't plugged in??

johnhoh · 16 Mar 2019

Windows is limited in this area, the solution is not perfect but should get the job done if you're only using the USB drives on a few computers. You just need to pick a letter for each USB drive that is NOT near the top of the alphabet, and then tell windows on EACH computer to assign that letter to the USB drive. You only have to do this once.

1) Choose three drive letters such as R: S: and T: (assuming you have three USB drives). Take a permanent marker and write the letter on each USB drive or put a piece of masking tape on the drives and write on the masking tape.

2) plug each USB drive into the first computer and do
start > run > diskmgmt.msc > right-click on the USB drive > select "change drive letter and path" > change > select R or S or T from the drop down menu. Name the first drive R: (or whatever), the second S:, the third T:

3) Do step 2 on EACH computer you will be using.

4) Once you have done steps 1 through 3, the drives will always have the correct letter on each of the computers, as windows will never use your letters for drive assignment since they are toward the end of the alphabet.

RoWin7 · 16 Mar 2019

And it won't do that with E, F, G, which is what I used in Disk Mngmt the first time around?

johnhoh · 16 Mar 2019

The problem with E/F/G is if you stick a different drive into one of the computers the E letter (for instance) may be assigned to it dynamically if C and D are already in use. Windows dynamic driver letter assignment is always the lowest letter not currently in use, so the only way to have a quasi permanent assignment is the method I outlined above.

Paul Black · 16 Mar 2019

Hi RoWin7,

johnhoh said:

Windows is limited in this area, the solution is not perfect but should get the job done if you're only using the USB drives on a few computers. You just need to pick a letter for each USB drive that is NOT near the top of the alphabet, and then tell windows on EACH computer to assign that letter to the USB drive. You only have to do this once.

1) Choose three drive letters such as R: S: and T: (assuming you have three USB drives). Take a permanent marker and write the letter on each USB drive or put a piece of masking tape on the drives and write on the masking tape.

2) plug each USB drive into the first computer and do
start > run > diskmgmt.msc > right-click on the USB drive > select "change drive letter and path" > change > select R or S or T from the drop down menu. Name the first drive R: (or whatever), the second S:, the third T:

3) Do step 2 on EACH computer you will be using.

4) Once you have done steps 1 through 3, the drives will always have the correct letter on each of the computers, as windows will never use your letters for drive assignment since they are toward the end of the alphabet.

I have used the method that johnhoh has described in the past, and it works very well.
It is important though to be able to identify which USB [external HDD] is which!

dg1261 · 17 Mar 2019

If johnhoh's suggestion isn't good enough for your purposes, you might take a look at Uwe Sieber's USBDLM ("USB Drive Letter Manager"). It installs as a Windows service, and controls which drive letters get used.

It's a pretty versatile utility. For instance, you can have it reserve a block of letters so Disk Management doesn't preempt them, and/or have it always assign the same drive letter based on device ID or volume label of the USB stick, or any of a wide array of other identifiers.

(I have no connection with Sieber, but have used his utility on a few computers and been impressed.)

RoWin7 · 17 Mar 2019

Johnoh-- it worked. I shifted them back and forth and the letters stuck. I realized the problem happened when I plugged in my external HD for imaging.