my "preview app" is always blocking

Hi ChrisJozef,

Thanks for the further details. It sounds like the app is frozen. There is likely no need to turn off the power. Try Force Quitting the app from the Apple Menu: How to force an app to quit on your Mac. Then, just restart your Mac as normal.

If the issue continues after this, see if Preview works inside safe mode: How to use safe mode on your Mac. This would let you know if a third-party app might be interfering with its function.

You can also test the issue in a new user account: How to test an issue in another user account on your Mac. This will let you know if the issue is isolated to your user or system-wide.

Let me know how it goes.

Have a great day!

Hi ChrisJozef,

It looks like no one has responded to your question. Here are a couple things that might help others answer your question:

Do you mean the preview app won't open?

Did you mean the image is "blocky"?

Please let us know as many details as possible.

Have a fantastic day!