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Mac OSX: How to Download, Install, and Start APT

Supported Systems

NOTE: APT is delivered as a native installer package on Mac OS X, so the download is named "APT.pkg".

APT is now bundled with Java 10 (starting with APT 26.1) and as a result requires Mac OSX 10.10 (Yosemite) or higher.

NOTE: APT on OSX 10.10 (Yosemite) needs to be started with a shell script or from the command line. See step 3 below. More recent releases do not have this issue.

APT requires a minimum of 512 Megabytes of RAM (memory), but we recommend 1 Gigabyte of RAM. Please see our memory discussion for more information.

Depending on your institution's computer security measures (firewalls, blocked ports, etc.), you may initially have communication trouble with APT. If you have any concerns please see our firewall webpage.

1. UnInstall the previous version

Note: If you are going to install APT in the same folder as a previous version, please remove the previous version first. But if you are going to install in a separate folder, you would only need to uninstall to save disk space (and possible version confusion).

To get rid of the old version: delete the entire folder where you installed it.

2. Download and Install

Choose your operating system: The installation page you enter next can choose the correct version for your machine for you - just click on the button that says "Download Now". (Or you can just choose the Mac OS X platform from the "Available Installers" table.) Then follow the instructions.

Proceed to the Installation...

3. Start

Once you have installed APT you invoke it by clicking on it. Go to the installation folder (default is in Applications/APT_26.2/) and double click on APT.

NOTE: APT has recently migrated to Java 10 and there is an issue with starting it using the top level ("APT") application icon under macOS 10.10 (Yosemite). APT will run correctly but will need to be started via a shell script. This may be done either directly from the finder (using the terminal icon found installed alongside APT as bin/apt) or from the command line.

4. Help

There is a a series of short training movies which will help get you started (there are also web pages with screen shots available on the same page). APT also has documentation available from the "Help" menu (the right most menu on the menu bar).

If you can't find what you need, please contact us at

How to find out about new releases

We maintain a distribution list for announcing new releases of APT. This may be helpful to people who install APT for others to use. Just send a blank email to: (Unsubscribe by sending a blank email to


If there are problems with the installation you can turn on debug logging and sometimes that will reveal the problem. (For instance one user found that there was a permissions problem and all that was needed was to run "Repair Disk Permissions"). This debug log would also be useful to send us if you can't figure out the problem. Contact us (through if you have problems with installation.

To turn debug logging on while running APT: