How to Install Old Software Packages on New Versions of OS X

Just like Windows version checks could have got hung up on checking Windows 95 and 98 with “9*”, Mac installers can hang on a check like this with the minor version number rolling over to 10 or more.

The installer package for my Blackmagic Design ATEM TV Studio contains this buggy version check in the Distribution file:

<script>function pm_volume_check() {
if(!(my.target.systemVersion.ProductVersion >= '10.6')) {
my.result.title = 'Failure';
my.result.message = 'Only target volumes containing Mac OS X 10.6 or later are supported.';
my.result.type = 'Fatal';
return false;
}
return true;
}
function pm_install_check() {
if(!(system.version.ProductVersion >= '10.6')) {
my.result.title = 'Mac OS X 10.6 or Later Required';
my.result.message = 'This installer requires Mac OS X 10.6 or later to run.';
my.result.type = 'Fatal';
return false;
}
return true;
}
</script>

Expand the package with this command:

pkgutil --expand Blackmagic\ ATEM\ Switchers\ Installer\ 4.2.pkg bm

Edit the script to just always return true to skip the check

<script>function pm_volume_check() {
return true;
}
function pm_install_check() {
return true;
}
</script>

Then repackage the installer like this

pkgutil --flatten bm Blackmagic\ ATEM\ Switchers\ Installer\ 4.2-fixed.pkg

Obviously, this won’t help if the software is actually incompatible with your OS version, and in a worst case scenario, could do some actual damage, but in my case, the software runs just fine on El Capitan. So, use this at your own risk.