P: Can't access some network files on Apple Silicon M1 Mac "because the file is locked"

While there are general issues with SMB and MacOS, this issue is specifically related to the Apple Silicone Macs. We’ve been using an SMB server workflow with our Intel Macs for years without any problems whatsoever. It’s interesting to me that Photoshop seems to be the only CC App that doesn’t play ball with servers on the new Macs.

I can confirm that the workaround posted by a user above is a viable solution for the moment. It seems that if the first PSD file opened is kept open, you can access any other files on the server without the error message. I might upset some people by saying this, but it seems like this might be a bug. And yes, I understand that the official Adobe answer is that Photoshop doesn’t support network drives, but that hasn’t seemed to present any unsurmountable problems until now. I’m trying to use highly qualified/diplomatic language here because this seems to be a touchy subject for some reason.

I’m looking into a hybrid workflow for our server setup where projects users are working on are synced between the client and server. An initial test seems to show that this is a potential solution as well.

Since Mac OS Big Sur, Apple has a known bug with SMB shares.
One work around that seems to work is to access the Share using credentials like:
smb://john:pass123@192.168.1.1/projects/

App: Photoshop 23.2.1

OS: macOS 12.3.1

Hardware: Mac with Apple M1 processor required to reproduce, Intel systems are not affected.

Files: .psd files stored on smb-fileserver, smb server system requirements not yet known.

Issue : When opening files from the server, occasionally Photoshop will display "Could not open "xxxx" because the file is locked, you do not have permission"  or "Could not open "xxxx" because of a disk error"

Occurance: Can be random but most times let you open files once but not again until network connection is re-established.

Workaround: Tt seems that the files do open without issues if you open multiple files at the same time. If opened individually it produces the error. 

Source, credit and more info:

https://community.adobe.com/t5/photoshop-ecosystem-discussions/photoshop-intermittently-cannot-open-files-from-our-server-on-apple-m1-big-sur/td-p/12343570

I added the a PPPC profile in our Apple MDM platform (see screenshot), and it seems to be working at the moment. We'll give this a shot and see if it makes a difference. The Network Volumes option is not available in the Privacy preferences pane but it seems that it can be added through a profile configuration. I'll keep an eye on things and reply back with results in case this is useful to someone else.

smb://username:password@[server_ip]/share/

For example:

smb://john:pass123@[192.168.1.1/projects/

On Mac M1 you maight need to connect to the SMB share providing user name:

smb://[username]:*@[servername/ip]/[share]/

We've tried both of those methods and both have the same outcome.

Just out of curiosity, are you opening the file directly from PS or from the PSD file it self?

I have a brand new Imac running Big Sur 11.5.1 with the Photoshop 22.5. When working from our work server, occasionally I Photoshop will display "Could not open "xxxx" because the file is locked, you do not have permission" etc. Or "Could not open "xxxx" because of a disk error" - these are files that I have been able to open previously in the same day or even hours before. I have to drag the files to my local desktop, and resave them back onto the server. The files are not locked, they are files created by myself. InDesign and Illustrator are fine - it seems to be a compatibility issue with Big Sur + the M1 Chip - but it's not listed in the Photoshop for Apple Silicon list of known problems. It's very frustrating!