Problem with external scratch disks in Photoshop CC

[chiara11]

Hi there!

I currently have problems with external hard disks in Photoshop CC  (Desktop PC with Windows 10 64 bit System) when it comes to using these as additional scratch disks. When I try to select the external scratch disk(s) via edit->preferences->scratch disks, the external hard disk often does not appear in the list, even if it has been correctly connected to the PC via USB. Sometimes it appears in the list after several tries like closing and re-opening Photoshop or disconnecting and re-connecting the external hard disk. I've had this problem for a while and would like to find out if  it is a Photoshop CC bug, and how it can be solved.

My Photoshop Version : 22.1.1 20210104.r.138 2021/01/04: 852879028a7 x64

Any advice would be appreciated, thanks!

[chiara11]

PS: I found a way to bypass the problem by continually pressing CTRL+ALT (Windows 10) when starting Photoshop... that way, a little window appears where I can select the scratchdisks. However, if someone knows how to fix the problem that I often cannot select any external scratchdisks via Photoshop itself (edit->preferences->scratch disks), your help would be appreciated, thanks!