I downloaded the latest stable JOSM package last night, after being prompted to update to the latest version, but then was not able to run the application. I received the rather cryptic error message “JOSM.app is damaged and can’t be opened. You should move it to the Trash.” What this actually means is that the Gatekeeper function in OS X 10.8 Mountain Lion was blocking the (unsigned) JOSM software.
To get round this, temporarily disable Gatekeeper by opening System Preferences > Security & Privacy, and set ‘Allow applications downloaded from:’ to ‘Anywhere’. Once you open the application, you can re-enable gatekeeper, and it appears that JOSM will open again without a problem. But this will likely have to be done for every update :(
I’m definitely not trying to blame the JOSM developers for not paying Apple for a developer licence to sign the software. In fact, they do a great job in continually developing the software to make it easier to edit OSM. Just thought I’d post this, in case it helps anyone else.
Comment from JohanWJoubert on 3 September 2012 at 10:09
Thanks for sharing! Johan
Comment from Vincent de Phily on 3 September 2012 at 12:26
If there’s any developers to blame, it’s the gatekeeper ones, for the misleading “error” message and the frightfull workaround.
Comment from ingalls on 3 September 2012 at 14:09
Yeah I second that. Gatekeeper is really a content control system, another way that apple is trying to get dominance through their app store. They can’t create a completely closed appsystem as they have with their iOS products but they are going to go down trying with their desktop software now too. All I can say is thank goodness I run linux!
Comment from skyper on 16 September 2012 at 22:27
Just for completeness the corresponding JOSM ticket.
Comment from jfire on 17 March 2014 at 18:18
I’ve filed an issue in the Apple bugreporter regarding the incorrect and misleading error message, and encourage anyone with the inclination and an Apple developer account to do the same. (Apple encourages duplicate reports as a means to gauge priority.)
Comment from jfire on 29 March 2014 at 20:19
My issue was closed with the following comment: “You are using an obsolete JavaApplicationStub which is stuck launching Java SE 6 and is deprecated. You need to rebundle the app with Java 7 (or 8), and resign the app using that.”