Learn what to do if a Mac application, such as Photoshop, Preview, or Mockuuups Studio, saves an unusable final file instead of a usable image (JPG, PNG) or project file.

I have a Setapp subscription, which gives me access to several pro Mac apps, and Mockuuups Studio is one of them, which I use every day to create iPhone, iPad, Mac, Android, TV, and other device mockups.

Recently, I was trying to export an image from the Mockuuups Studio app, and the final file saved in Finder had weird names, was grayed out, and was pretty much unusable. None of the apps could open it.

In my case, the issue was with Finder, not Mockuuups Studio. I will show you how to fix the issue, along with several other important solutions.

Some files can run into several MB and take a while to export. Keep the app open to ensure it has exported fully.

Many apps show the usual macOS ‘save’ dialog box before the file is exported and saved. Even when you’re in a hurry, make sure you rename the file properly and don’t accidentally delete or edit the file extension (.jpg, .png, etc.).

In case you changed or deleted the extension, rename the file in Finder and add the correct one.

This is what worked for me.

Even after exporting the same file multiple times, I noticed that the final what-should-have-been-a-image-file had a long, weird name that appeared grayed out in Finder, as if it were a hidden system file. There was no way I could open that file in Preview or upload it to Canva. Thankfully, a simple Finder refresh fixed the problem:

1. Click the Apple icon  in the top-left corner, then select Force Quit.
2. Select Finder and hit the Relaunch button.
3. Open Finder, and you should see that the file you exported is indeed a normal image file.

If you haven’t already, delete the unusable file in Finder first. Then, quit or Force Quit and reopen the app (Photoshop, Mockuuups Studio, etc.) and export the image or project file again. The file should be what you expect.

In case the above solutions have not worked for you, save any unsaved work and reboot your Mac.

Go through these remaining solutions, which can take a bit longer:

• Open the app and check that you didn’t change the export settings.
• Try editing the project or using a different source image, and then try exporting it again.
• Duplicate the project in the app and try exporting that. Make minor changes and export it.
• Update the app from the Mac App Store, Setapp, or the developer’s website as appropriate.
• Delete and reinstall the said app.
• Update your Mac to the latest version of macOS.

What issue were you facing, in which app, and which solution worked for you? Share with us all in the comments section below.