App no longer opens on other OSX machines

Hello again all,

I have an app that I have been working on for 2+ years for OSX - I host it on my website as a zip file for download.

Since I’ve moved to OF v11, when I (or anyone else) tries to download and run the app, I get the following message:

app is damaged and can’t be opened. You should move it to the Trash.

How can I fix this? Is it code signing related??


Hi, which version of macOS are you on?

You might need to disable code signing as described here:

I think if you are signing the app for development ( which is the default now ) it might error on other machines.

Going forward if you want to distribute your Mac App ( and even currently if you don’t want warnings when users open it ) you’ll need to sign the app for distribution ( and starting in 10.15 notarize it too ).

hey, thanks for the reply…

I’m on Mojave, 10.14.6; but others who use the app are on 10.15 as well I think.
Is there a (idiot proof) guide to signing an app and notarising it in OF? I’m totally new to all of that


edit: I don’t think it is the linked issue, I’ve tried that and I still get the warning. I think it is probably Gatekeeper blocking the app from running because of signing, which I’m a bit lost on how to do properly.

I think it is all covered here:

It is the same for OF and any other app made in Xcode.

thanks… I think!
Seems quite a bit beyond what I am familiar with.

edit: (having read up) Am I right to think that I have to pay ££ to Apple in order to get a developer membership, or it is no dice?


Yes, sadly as things currently stand from 10.15 onwards ( after an update in Jan 2020 ) you will need to pay Apple $99 a year to distribute outside of the AppStore.

For now I think if you do Build->Clean from the menu and change the “Sign to run locally” to nothing as in Todd’s post you should be able to run the app on other platforms by right clicking or control clicking on it and selecting open. That should allow you to bypass the Gatekeeper restrictions.

this could be related to translocation problem.
There is some topic related to this:
I am using this app (dmg canvas) to make a simpler .dmg:

@moebiussurfing thanks for this, but I’m pretty sure my data files and so forth are fine, I bundle them up into the app and include: ofSetDataPathRoot("../Resources/data/");

@Theo I’ve tried the blank ‘sign to run locally’ option and yes, this now runs on other Catalina installs (with a little help from right click, open). Thanks for this, I was a bit panicked!

I guess I have to ask Father Christmas for an Apple developer licence. That stings more than a little bit, given I give the app away for free. Might there be any issues with signing and notarising an app with things like shaders, csv data file loads, etc included in it? I’m worried that I end up shelling out the ££ and still can’t fix the problem.

Hey @Sam_McElhinney_io. I am not sure… but maybe you can take a look to the translocation problem. just in case… It’s not related to where the data is located, inside or outsite the Sorry to say it again but I had the same problems (in 10.13 not Catalina like you…) and that links solved them for me.