I can't open ANY application from finder because it may be " damaged or incomplete" which is not the case as they open occasionally from other apps.
When I try to open an application using the dock, finder window "Applications", launchpad, recent items or even by trying to open any particular given file directly, I get the message:
"You can't open application 'application name' because it may be damaged or incomplete."
which effectively cripples my entire iMac. The only way I've been able to open an app is occasionally from another app. Eg. A link to a website in an email may open Safari And form there Safari works exactly like it should. But there seems to be no consistency in this being a sure fire way to open anything.
I have installed macOS updates, reinstalled the macOS from a copy downloaded from the AppStore on another computer, I have booted in safe mode and performed RAM clearings and I just can't ditch this bug.
This started after I'd filled the hard drive to an almost critical level apparently resulting in the OS seeming to wipe all my internet accounts (or at least my access to them) with out actually wiping them yet not permitting me to reconnect them saying they were already there.
I'm running an iMac 27" 5k Retina display, late 2015 with 3.2GHz Intel Core i5 with 8GB memory and a 1TB fusion drive with macOS Sierra 10.12.5 installed and a Bootcamp partition running Windows 10.
iMac with Retina 5K display, macOS Sierra (10.12.5), 27inch