Hi Steven,
The new Server version 2.7.9.0 is available for download. If you are updating from 2.7.8.0 you may still need to restore permissions in your server book. If you have a simple permissions structure, i.e. one account that has full access to the entire book, just do the following:
1. Update to 2.7.9.0 "as is", i.e. just run the installer and complete the installation.
2. In the server address book manager expand Address Books, right click on your address book and select Edit address book.
2. Click Security.
3. In the security window enable Replace all child object permission entires with inheritable permission entries.... This will grant the account (principal) in the list permissions to all objects in this address book and restore permissions for the entries where they were deleted due to the bug. Therefore, when you sign in on the Viewer your "lost" entries should re-appear in Viewer address book.
If you have more granular access levels, i.e. other accounts with access to only some folders you will need to do the same procedure but on the respective folder level.
Let us know if you need any assistance.