Safari on my Mac won't open because "Safari cannot be opened because of a problem. Check with the developer" I have an error message, which has already been reported but I can't understand how to fix it. 

I have Yosemite and there's no updates available except for iPhoto, which also can't be updated. I'm also locked out of Safari and all of my Favorites. I don't know if they're backed up in iCloud, but I'm really worried about this. Can anyone help me by providing the dumbed-down version? Here is the message I get:


  Safari cannot be opened because of a problem.
  
  Check with the developer to make sure Safari works with this version
  of OS X. You may need to reinstall the application. Be sure to install
  any available updates for the application and OS X.
  
  Click Report to see more detailed information and send a report to
  Apple.


Restarting the computer does nothing, and I'm afraid to reinstall without knowing what will happen to my data.
Looks like you updated iTunes and this is the aftermath.

https://www.macrumors.com/2018/12/14/itunes-12-8-1-breaks-safari-on-osx-yosemite/

I hope this helps you