Cannot save Screenshots to External Drive

You may need to give the screenshots app Full Disk Access.

this suggestion is based on my experience with saving recordings, but it may apply to screenshots as well as the two are somewhat related.

I have, in the past, encountered issues with longer recordings stopping / not saving unexpectedly whenever I have selected anything other than "desktop" as my "save to" location. this has been especially true when "save to" is set to an external drive. so I now use "desktop" as my "save to" every time and afterwards I move them to my desired location manually. I haven't had an issue since.

To expand on HWTech’s theory.

What happens if you save the Screenshot on the Desktop, then copy it to the external drive..

Yes, I just discovered this on Sequoia. It worked until very recently (last few days and probably since any macOS update installed a few weeks ago). I've had Sequoia set to save to a folder on an external drive ever since starting to use Sequoia 4 months ago, but today it started displaying the message in the first first post. If I reset the destination to "Desktop" it saves without issue. I tried giving the Screenshots app full disk access but it still won't save. I haven't tried restarting the computer. You oddly have to do that weekly with Sequoia to clear up odd glitches. I remember when using Tiger OS I left the computer running for almost a year without ever restarting it.

den.thed wrote:

To expand on HWTech’s theory.

What happens if you save the Screenshot on the Desktop, then copy it to the external drive..

I can do that without any issue, but it is a nuisance having to open the folders, copy, and then delete the one on the internal drive.

I am absolutely certain this was working not long ago. Probably in the last week or two since every few days I end up doing a screenshot of something. It was just today that it popped up that error message. The external drive was awake. In fact after getting that message I did some things with files on it just to make sure it was awake, but when I did another screenshot it didn't work. Switching to the Desktop worked. Switching to a different folder on the external didn't work. I don't think there has been any kind of software update recently (I have it set so that I have to manually apply them). The one thing I haven't tried yet is rebooting the computer. I only switched from High Sierra to Sequoia a few months ago and this is not the only —dare I say it?— bug I have encountered. For several others a reboot cleared up the issue. I'm just more used to that being an iOS kind of thing. :-)

Edit: Nope, rebooting didn't get it to work.

Limnos wrote:

I can do that without any issue, but it is a nuisance having to open the folders, copy, and then delete the one on the internal drive.

Yeah' unlike many, I run a file and folder free desktop. Which makes it easy to send new screenshots to the desktop, then copy them to a different location and trash the originals.

FWIW I'm running Sequoia 15.7.3 and I was able to direct screenshots to both my Media Drive and to a folder on a 128GB Memorex Flash Drive that is formatted APFS using the (Command Shift 5) Options.

If it is not a security or permissions issue, then it may just be that Apple doesn't want macOS to have selected the default location to be on external media that may not be available all the time since external media can disappear (intentionally or accidentally).

I have the same issue in Tahoe. Already granted full disk access, but it doesn't seem to help.