This issue happens only with MAC.
When using external hard drives, you may run into an issue that prompts DxO PhotoLab 4 to warn you that you have an invalid configuration. This happens because DxO PhotoLab 4 is using the volumes’ Unique Identifiers (UUIDs) to uniquely identify drives, regardless of their names, as you could have volumes with the same name. If you’re shown this warning, it means that some of your volumes have the same UUID, preventing OpticsPro to uniquely identify your volumes.
To check the volume UUIDs, here is what you should do:
- In the Apple menu, choose ‘About This Mac’.
- Once there, click on the ‘System Report…’ button.
- On the left, in the ‘Hardware’ section, select the ‘Storage’ item.
Once you click on 'Storage', you will see a list of drives and other storage devices currently attached to your system. As each device is selected, you will see its information, including the UUID, listed in the lower window.
To see all of the devices listed together, click once on the top device listed in the upper window, hold down the Shift key, and click once on the last device in the list. You will see all of them listed together in the lower window. You can then check the UUIDs there.
Unfortunately, this is something pretty common if you happen to buy 2 hard drives of the same brand and model, as manufacturer usually just clone volumes from a template to their new hardware, thus replicating the same UUID across multiple devices. It can also happen if you clone a volume from one hard drive to another yourself using some specific software.
If you are in this configuration and you use DxO PhotoLab 4, you may end up not being able to display images in OpticsPro using those volumes. Opening some folders, DxO PhotoLab 4 will tell you that no images are present, while you know there are some.
There are a few ways to resolve this issue:
- Reformat one of the drives, so that it is given a new Unique Identifier. Be extremely careful, because reformatting will erase all data on the drive, so you will have to back it up on another drive before doing that operation.
- If you have the technical knowledge to do so, or can be helped by someone to do it, you can change the Unique Identifier of the drive without reformatting, by using the comment line tool ‘hfs.util’ with the ‘-s’ option. However, you should be sure of what you’re doing before attempting this, and we would recommend that you back up your data anyway, to be sure you’re not losing anything.