I have Address Book 6.0. I can't load it on my new computer. Do you have an upgraded version that works with Windows 7, and will it read the files created by Address Book 6.0?
There was a new version (7.0) that worked well with Vista and above but that version was discontinued some time ago thus making it unavailable for download from its official website. You might want to check Amazon or Ebay to see if someone sells it.
