[messages] [Technical Support & Bugs] Vassal under Apple Catalina

Malnorma malnormacxio at gmail.com
Sun Oct 20 04:04:24 CEST 2019

I think this is part of Catalina's general paranoia about
unsigned/un-notarised/downloaded applications, possibly worse for being
Java-based.  On first run, Vassal attempts to open the modules in the
recent list to verify they exist, and this action seems to be quietly
(i.e. no user prompt) blocked by the system.  Once you've added a module
through the file dialog, everything is fine until the next reboot.

In any case, I found a few ways around it.  The easiest one is just to
remove the quarantine attribute from the application with this command
(paste this into Terminal.app):

xattr -d -r com.apple.quarantine /Applications/VASSAL.app

If this fails due to permissions, run it as

sudo xattr -d -r com.apple.quarantine /Applications/VASSAL.app

and provide your password when prompted.  You are effectively convincing
the OS that the app was not downloaded from the internet, and can be
allowed to access files in your home directory.  You will need to do
this for any new build you download and copy into /Applications.

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