External Drives not available for scratch disk in Photoshop after Catalina

[StevieDan]

After upgrading to Catalina, I can't add External Drives for scratch disk space in Photoshop. I read several threads on this subject and did the recommended fixes: adding Photoshop to my Mac Mini's (2018) Accessibility in Catalina's (v. 12.6) Security & Privacy, also added PS to Full Disk Access. I dragged the Photoshop 2022 system preferences folder from my user name > library > Preferences to the desktop and restarted Photoshop. None of this fixed my issue, which is that the external hard drives aren't showing up in Photoshop's scratch disk preferences panel. Those external drives are at 10 TB G-Drive Thunderbolt formatted as Mac OS Extended (Journaled) and a LaCie 10 TB Thunderbolt drive formated as Mac OS Extended (Journaled). I have never had this problem before Catalina, which is exactly what seems to be the catalyst for this phenomena's sudden appearence. What should I try next? 

[PECourtejoie]

Hello, If I Remember Correctly, Photoshop requires the drives to be recognized as non-removable by the OS to be able to use them as scratch disks, I'd investigate in that direction.

[StevieDan]

I've been using external hard drives as scratch disk since Photoshop 2. Never saw this issue until upgrading to Monterey 12.6. I can see them in the finder. I can launch files, but I'm not sure what you mean by non-removable.

[TheDigitalDog · Accepted solution]

In System Preferences, >Security & Privacy, >Full Disk Access, do you see Photoshop listed? If not, add it and try again.

This expalins how to do the same process in Lightroom, just pick Photoshop instead:
https://community.adobe.com/t5/lightroom-classic-discussions/quick-tips-how-to-give-full-disk-access...

[Tellulah2]

thedigitaldog

Thank you. This worked for me without having to do 10 other things first. 

Simple quick fix and my scratch disc is now SSD

[D Fosse]

The most likely reason is still exFAT formatting, which doesn't work well (or at all) on recent MacOS versions. It used to work, and was originally intended as, cross-platform between Windows and MacOS.

Reformat to APFS. This will of course wipe the drive, so if there's content you want to keep, copy it off the drive first.