Ilastik app can't be opened on mac catalina

Hi, I have a working version of Ilastik on my mac (ilastik-1.3.2rc2-OSX on Catalina 10.15.3). I’ve tried to download a new version of ilastik a few times, but am getting a “can’t be opened” error. This does not appear to trigger mac security as I can’t allow it through the osx security & privacy settings. Here’s what the error looks like with a fresh download from either the main ilastik download link or from the mirror. I’ve tried this from home and from work so the network connections have been different:

Screen Shot 2020-03-09 at 4.52.55 PM

thanks for help with this problem! John

have you tried opening it with right-click and open?

I have. The error is slightly different:

Screen Shot 2020-03-13 at 9.15.16 AM

I’ve tried to download a few times. -John

this is a different download after right click > open:
Screen Shot 2020-03-13 at 9.18.10 AM

hey @johnmc,

I found a this thread on StackOverflow where they claim the solution is changing the executable flag of the files in folder. Would you be comfortable in trying this in the terminal?

okay hang on, I checked the files and they already have the right flags - sorry. Nothing to try out just yet

This sounds a lot like the problem that has recently beset QuPath on macOS… basically, you may be being thwarted by a recent security change and a resulting quarantine flag.

There are a couple of ways around it - none of them great, but they have worked for me. You can see them at

If it’s the same problem, I’d love to discuss with other open source developers here how to cope with this new security behavior on macOS…

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Hey @petebankhead, thanks a lot for picking this up, I was about to write to you :slight_smile:

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Hi Guys, Thanks for looking at this. I’ve tried Pete’s suggestions, but they didn’t help. I did this:

curl -O
bzip2 -dc /Users/me/Desktop/ilastik-1.3.3post2-OSX.tar.bz2 | tar xvf -

but I get the same error message as above (“can’t be opened” after right click > open or whatever).

Then I tried this:

xattr -d /Users/me/Desktop/

but it didn’t help. I’ve get a call out to my IT/unix expert. If they have a helpful suggestion I’ll pass it along.

thanks again for your time. -John

thank’s a lot for letting us know @johnmc. On my mac (10.13.5) I can open it. Would appreciate any update from you!

ah, I should have asked IT first. Our company uses Cylance and it was blocking the install. Now it works! Sorry for the hassle. Love Ilastik, thanks for all the hard work! -John

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Didn’t know about Cylance! Great that you found the solution :)) have a great weekend!