Catalogs External backup drive letter designation (Windows)

[philromford]

Lightroom Version

Lightroom Classic CC

Operating System

1. Windows 7
2. Windows 8
3. Windows 10

I have seen mention of when using external drives on Windows PCs, that the drive letter may change when swapping into different PCs. This is something I do. If Windows assigns a different drive letter than that when photos are added to a catalogue, Lightroom cannot find them. The solution is simple:-

Right click the Windows Start button, select Disk Management to bring up the overlay.

Select the backup disk, in this instance 'D', right button click and select 'Change Drive Letter and Paths' to bring up a dialogue box; in it you will see the current drive letter.

Click on Change to bring up a new dialogue box,

in which a new drive letter can be assigned. Click on the selection box. I am going to select drive letter 'H' then click OK. This will bring up a warning overlay:-

For our purposes this is not an issue assuming that this drive is dedicated to Lightroom only, click on Yes.

You can see that the drive letter is now 'H'.

Before doing all this, ensure that the new drive letter you wish to use is actually available to use on each PC. That is easy to do, by simply checking with File Explorer to see the active drive letters.

Doing all the this removes the headache of missing photos when swapping PCs. Do not be tempted to find lost photos by using the Lightroom find photo option, you will only have to do it all over again when you swap the drive into another PC, thus perpetuating the headache.

I have done this and have had no issues for some years. The PCs remember the drive letters I have assigned.

There is probably a Mac method of doing this too.

I hope this helps you.

 

[Johan Elzenga]

There is probably a Mac method of doing this too.

There is no need for this on a Mac. Macs don't use the archaic drive letter system, they use a disk name. You give the disk a name, and then it will have that name on any Mac you connect it to.

 

[philromford]

There is no need for this on a Mac. Macs don't use the archaic drive letter system, they use a disk name. You give the disk a name, and then it will have that name on any Mac you connect it to.

I learn something every day. I no nothing of Mac computers. Thanks for that.

 

[clee01l]

I learn something every day. I no nothing of Mac computers. Thanks for that.

FWIW, Microsoft Windows is the only operating system that uses and assigns drive letters to disk volumes. Every other operating system (MacOS, UNIX, Linux, SunOS, AIX) uses volume names.
Originally DOS Drives A: & B: were reserved for removable media (floppy). and assigned when found on boot. When permanent disks were installed the first found drive letter was Assigned to C: and A: & B: were ignored. Subsequent volumes discovered on boot were assigned drive letters in the order they are discovered. That meant that Drive D: became the installed optical drive and thumb drives and card media were assigned when inserted. It was at this point when the weakness of the drive letter system became apparent. Microsoft kludged the reserved drive letter to a named volume to which is what we recommend here to keep LR from losing its place. This works until the boot process assigned a found unassigned volume to a reserved drive letter before the reserved volume is mounted. Also recommended is to assign reserved volumes from the end of the alphabet (Z:, Y:, X:, etc) As these are unlikely to get assigned during the discovery boot process. Windows will never automatically assign A: & B: but these are still valid drive letters and can be used for permanentlymounted volumes. This is problematic though since some poorly written apps ignor A: & B: and begin searching at C:

 

[philromford]

FWIW, Microsoft Windows is the only operating system that uses and assigns drive letters to disk volumes. Every other operating system (MacOS, UNIX, Linux, SunOS, AIX) uses volume names.
Originally DOS Drives A: & B: were reserved for removable media (floppy). and assigned when found on boot. When permanent disks were installed the first found drive letter was Assigned to C: and A: & B: were ignored. Subsequent volumes discovered on boot were assigned drive letters in the order they are discovered. That meant that Drive D: became the installed optical drive and thumb drives and card media were assigned when inserted. It was at this point when the weakness of the drive letter system became apparent. Microsoft kludged the reserved drive letter to a named volume to which is what we recommend here to keep LR from losing its place. This works until the boot process assigned a found unassigned volume to a reserved drive letter before the reserved volume is mounted. Also recommended is to assign reserved volumes from the end of the alphabet (Z:, Y:, X:, etc) As these are unlikely to get assigned during the discovery boot process. Windows will never automatically assign A: & B: but these are still valid drive letters and can be used for permanentlymounted volumes. This is problematic though since some poorly written apps ignor A: & B: and begin searching at C:

Yes, it's interesting that Microsoft have never caught on to this method. Personally, I have no problem with it, as I know how it works. This is why I thought I would create my post, as a helper for those who do not know these things - and struggle.

 

[Philippe Coudé du Foresto]

In fact, Windows CAN use folder to mount volume instead of letter. It's what I use and do not assign letter to to my drives, USB keys, etc.

As youn can sse in the above screenshots, there is an an option called "Mount into the following empty NTFS folder". Use it instead of "Assign the following drive letter".
On my system, I've created a root folder called "External" into which I've a subfolder per device (with the same name as the device). I use this folder path in all applications (LR, Backup, etc)