• Long time Mac user but never had this problem before and it's driving me nuts.

Every time I open a file by double clicking on it, it will refuse to open if the application is already open. Weirdly it will do the quick icon expanding flash you see when you open a file, but it wont load.

I will need to quit the app, then open the file again for it to open. Then, once in the application I can select open from the pull-down menu which works.

It is happening on all types on applications not just one, Photoshop, Excel, Word, Preview, Quicktime etc

I then attempted to show this to a friend and it completely stopped happening for a few hours (sods law) at that moment! It does seem to momentarily start working again.

How might I resolve this weird behaviour?

  • Firstly, welcome to Ask Different! :) Can I ask what, if anything, you've already tried in order to resolve this? Otherwise you may get lots of suggestions for things you've already tried. Also, what version of macOS are you running?
    – Monomeeth
    Commented Sep 10, 2019 at 10:45

1 Answer 1


There's a few things to try here to help us narrow down this problem.

Boot into Safe Mode

Follow these steps to boot your Mac into Safe Mode:

  1. Fully shut down your Mac
  2. Restart your Mac
  3. Immediately press the Shift key and keep it down
  4. Let go of the Shift key when you see the login window
  5. Now log into your Mac and (NOTE: If you have FileVault enabled you may need to log in twice)
  6. Now test to see if you have the same problem
  7. Exit Safe Mode by restarting your Mac as normal
  8. Once again, test to see if you have the same problem

Once you've done this let me know how you went and we'll go from there.

  • Thanks for the super fast response! :) I'm on Mojave at the moment, and so far all I have really tried is system updates and looking into any 3rd party extensions that may be affecting it. I had Parallels running and played around with this being on\off, and seeing if it was an issue with the troublesome app being open in another desktop. Ill try the safe mode as suggest and let you know! Commented Sep 10, 2019 at 11:12
  • I would start by creating a new user an use that before safe mode
    – mmmmmm
    Commented Sep 10, 2019 at 15:54
  • @Mark Yeah, that's my next step if booting into Safe Mode doesn't make any difference. :)
    – Monomeeth
    Commented Sep 10, 2019 at 22:41
  • Did the safe mode method and its seemed to have completely cured it! - Thank you so much :) Would have never thought of that. Commented Sep 14, 2019 at 15:08

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .