Thank you to all for the suggestions received about this problem. Here is how I fixed it.
I created a test account and had a look at what existed before Address Book had been opened. I determined that the entire folder called AddressBook at Library/Application Support is not created until the first time Address Book is opened. I dragged in a good AddressBook folder copied from another account and the Address Book application immediately adopted it when booted. I then went into the problematic account and removed the dodgy AddressBook folder to Trash and restarted the computer. Repeating the previously tested sequence, I placed the known-to-be-good AddressBook folder into Library/Application Suppport. It has again been adopted okay. Phew. Another triumph for humans over machines. The incident appears to have happened to me as a result of the Snow Leopard install. I suggest people who are yet to install Snow Leopard first make a copy of the entire AddressBook folder and/or do an exported copy of the list of contacts. This option is found under the pull-down menu ‘File.’ A exported list done a couple of days before my Snow Leopard install saved my bacon. Kind wishes, Paul. -- The WA Macintosh User Group Mailing List -- Archives - <http://www.wamug.org.au/mailinglist/archives.shtml> Guidelines - <http://www.wamug.org.au/mailinglist/guidelines.shtml> Unsubscribe - <mailto:wamug-unsubscr...@wamug.org.au>