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In theory, the Download Manager, being Java based, will work on any operating system. We have tested on various flavors of the Windows, Linux, and Mac OS X operating systems. We are fairly confident that the Download manager to run on any of these operating systems; however, the Mac OS X operating system has been imposing additional security requirements on Java Web Start programs, such as the Download Manager, which make them difficult to run unless the user has administrative access to the Mac. In particular, the Gatekeeper function in 10.8.4 (Mountain Lion) and later versions of Mac OS X, including 10.9.* (Mavericks) by default blocks starting third party programs that have not been either obtained from the Apple App store, or signed with an Apple Developer ID. This includesimpacts, naturally, Java Web Start programs such as the Download Manager. To get around this restriction, one can either change the default Gatekeeper setting, found in the Security tab of Apple System Preferences, to allow the running of 3rd party applications, or download the JNLP file used to launch the Download Manager, and then command | control | right click the JNLP file and select "Run" from the pop-up context menu. Double clicking the JNLP file will not work with the default security settings on the later versions of Mac OS X. Note that either method requires either having administrative access to the Mac OS, or knowing the username/password of an administrator account, since the Mac will prompt for this information.
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