Update to QuarkXPress 7.5 or upgrade to QuarkXPress 8. If these are not options for your site, follow these steps to resolve this issue:

  1. Restart the computer to clear all system resources.

  2. Launch Activity Monitor (Mac HD > Applications > Utilities > Activity Monitor).

  3. View All Processes.

  4. Quit any process that includes the name 'rsync.'

Background: After a force quit, QuarkXPress is holding onto certain system resources. This is a defect in QuarkXPress 7.31 and 7.4 and no longer occurs in QuarkXPress 7.5 and 8.x.