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romanof

macrumors 6502
Original poster
Jun 13, 2020
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Texas
Been trying the Big S for a day or so and it works fine on an i5 iMac, except...
Screen saves and records will not save to an external usb drive, whether formatted in AFPS or Extended journeled. Tried a spinning disk and an SSD.

"Your screenshot can't be saved.
Cannot write file to intended destination."

Other utilities, including Final Cut Pro X write to them just fine.

I can't affect it with the permissions or anything in the Get Info pane.

Bug in the Big S or is there some obscure permissions flag new to this version?
 
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gilby101

macrumors 68030
Mar 17, 2010
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I have not such problems with the in-built screenshot app.

I suspect your problem is not file permissions, rather rights of the screen recording app to write to an external drive. Are you using the in-built screenshot app or something else?
 

romanof

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Jun 13, 2020
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I have not such problems with the in-built screenshot app.

I suspect your problem is not file permissions, rather rights of the screen recording app to write to an external drive. Are you using the in-built screenshot app or something else?
The built in app. Cmd-Shift 4 or 5

Movavi Screen Recorder saves ok. Has to be some perimeter in screenshot. Just not sure where to look.
 

gilby101

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Mar 17, 2010
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I have not such problems with the in-built screenshot app.
I take that back. And the bit about permissions. What I have found:

1. The screenshot can be saved to an external disk so long as you have write permissions to the top level of the drive.

2. The screenshot can NOT be saved to an external disk when you don't have write permissions to the top level of the drive and you just click a folder or use the disclosure triangle to select a lower level folder. Is that a bug? I think so. But...

3. The screenshot can be saved if in the destination selection dialog you double click on the destination folder. Then the Choose button becomes enabled!!
 

romanof

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Jun 13, 2020
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Ok. I am not following your explanation. The permissions at the CLI level for that drive are 777. Read/write for everything. Does that not set full permissions from the top down?

Disclosure triangle on what? I know what it is, but I don't see one on anything related to the problem.

Tried granting Full disk access to the Screenshot app, but that didn't work either.

Thanks. At least I know now that I haven't hoked up my system, if you see the same thing.
 
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gilby101

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Mar 17, 2010
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By default a newly formatted external disk will show:
ls -la /Volumes
drwxrwxr-x 22 root wheel 816 20 Nov 19:37 MyBook6A
[I have just shown one line from many in the output]
On that drive the screenshot location 'Choose' button is disabled because you are not root and not in wheel group and everyone only has read access.

What happens next depends on the view. I am assuming that you do have the correct permissions and ownership on at least some folders. Like this:
ls -la /Volumes/MyBook6A
drwxr-xr-x 11 gilby staff 374 13 Oct 18:00 MyBackups
[Just one line of many]. I am owner and have rwx permissions on that folder.
Icon view:
At the top level select the folder (click on it) and the Choose button is disabled.
Open the folder (double click) and the button is now enabled.
List view:
When you look into folders using the disclosure > (not triangle), the Choose button remains disabled.
Again you have to double click on a folder to open it and the Choose button is enabled.
Column view:
Just a single click (which is an open) on a folder is enough to enable the Choose button.
 
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romanof

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Jun 13, 2020
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Thanks for your time, Gilby.

My drive has the proper permissions, just like yours...
drwxrwxr-x 6 krf staff 192 Dec 5 16:21 SSD1

And the Choose button acts exactly as you describe, in either Icon or List view. It appears on click and I select it and it puts the external drive as the target for the snapshot. But I still get the message popup on capture saying that I don't have permission.

What is interesting, is that every other program on the machine can write to external drives without issue, so the proper permissions have to be there. This has to be an issue with Screenshot. But I have searched the world for any settings, but found nothing. Either I am the only one having the problem - and thus it is a bug in my install - or Big Sur is too new for a minor problem issue to be posted as yet.

I have a new Mini that will be here in a week. If it fails there, then it is an Apple problem. If not, then my install on this iMac is bugged.

It almost looks like a security glitch, with Big Sur saying you can't post snapshots to some unknown place that can just walk away. I have certainly hit enough security popups in the last two days. The only one missing so far is the requirement to clicking ok prior to getting up for more coffee. Almost reminds me of Vista, may dogs grub up the bones of whoever wrote that disaster.
 

gilby101

macrumors 68030
Mar 17, 2010
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And the Choose button acts exactly as you describe, in either Icon or List view. It appears on click and I select it and it puts the external drive as the target for the snapshot. But I still get the message popup on capture saying that I don't have permission.
There must be something else. I can screenshot to any folder (or top level of a drive) that I have permission for. If the Choose button is enabled (and I click it) then my screenshot goes to that destination without any problems.

I can't see anywhere else to configure this. And, as you have found, no mention of it on the web. Seems like there is something wrong with your install. But I have no idea what.

I expect it will work with you new Mac Mini.

This is macOS 11.0.1 on Intel iMac.
 

romanof

macrumors 6502
Original poster
Jun 13, 2020
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Texas
It's a problem with the Big Sur load on the iMac. Brand new Air received yesterday and set up and Screenshot works fine with external drives.
 

k9gardner

macrumors newbie
Mar 21, 2015
14
3
There must be something else. I can screenshot to any folder (or top level of a drive) that I have permission for. If the Choose button is enabled (and I click it) then my screenshot goes to that destination without any problems.

I can't see anywhere else to configure this. And, as you have found, no mention of it on the web. Seems like there is something wrong with your install. But I have no idea what.

I expect it will work with you new Mac Mini.

This is macOS 11.0.1 on Intel iMac.
Thanks for your time, Gilby.

My drive has the proper permissions, just like yours...
drwxrwxr-x 6 krf staff 192 Dec 5 16:21 SSD1

And the Choose button acts exactly as you describe, in either Icon or List view. It appears on click and I select it and it puts the external drive as the target for the snapshot. But I still get the message popup on capture saying that I don't have permission.

What is interesting, is that every other program on the machine can write to external drives without issue, so the proper permissions have to be there. This has to be an issue with Screenshot. But I have searched the world for any settings, but found nothing. Either I am the only one having the problem - and thus it is a bug in my install - or Big Sur is too new for a minor problem issue to be posted as yet.

I have a new Mini that will be here in a week. If it fails there, then it is an Apple problem. If not, then my install on this iMac is bugged.

It almost looks like a security glitch, with Big Sur saying you can't post snapshots to some unknown place that can just walk away. I have certainly hit enough security popups in the last two days. The only one missing so far is the requirement to clicking ok prior to getting up for more coffee. Almost reminds me of Vista, may dogs grub up the bones of whoever wrote that disaster.
Just a small reality check jumping ahead a few years; I'm using a new Mac mini (M1), running Monterey, and having the problem mentioned by the OP, romanof. I've got all the same permissions, 777 at root level of the external drive. I can "Choose" the root level, or any folder within it. And I have rwxrwxrwx all the way down the line. I've also added Screenshot to Full Disk Access. And yet... I cannot save screenshots to the external drive. So I don't think the solution was what was proposed here.
 
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