Time Machine Account Settings Question in Airport Utility V6

Question

Hi, I recently upgraded Airport Utility to V6 in which they now have a settings for the builtin Time Capsule to set Secure Shared Disks.  The settings are:
     1)  With Accounts,
     2)  With a disk password,
     3)  With a device password.
When I setup my Time Capsule I used  "disk password".  When I upgraded the Airport Utility to Ver 6, I switched from "disk password" to "with Accounts" for the Time Capsule backup.  The trouble was after the switch, all prevous backup on the TC were no longer available.  So I changed the settings from "with Accounts" back to "disk password".  All previous backups were not visible anymore from within "Enter Time Machine" space.  Fortunately when I changed it back to "with Accounts", I can access the recent backups but not those prior to the switch.  Can anyone help me so I can have a better understanding of how this settings work and its effect on the backups.  I thought that was only a security issue which should not affect the backups.  Thanks in advance.

Answer 1

Take a look at this: http://docs.info.apple.com/article.html?path=Mac/10.7/en/mh21241.html
For improved security when backing up to a Time Capsule, the Time Capsule administrator can enable account mode and create individual accounts on the Time Capsule. Each Time Capsule account has its own network volume and password. If you back up to an individual account volume on a Time Capsule, other users can’t access your backups unless they know the password for that account.                                  Note: A Time Capsule set up with individual accounts contains a shared volume. Be sure you select your ownindividual volume as your backup disk, using the account name and instructions given to you by the Time Capsule administrator. The shared volume is intended only for information that all users canaccess.
With account access, each user gets his/her own volume, I assume, on which the Time Machine backups are stored.
My Time Capsule isn't set up yet, but I was playing with those settings. I *suspect* what happened when you switched from disk to account access is that there was sometime of (virtual?) repartiting taking place; for you went from one large partition (disk) to separate partitions (for each user). If that is right, big *if*, the original backups *may* be gone -- although there may be a way to recover them.
Were I you, and if those backups matter, I would stop using the Time Capsule for backups -- turn off Time Machine on all clients -- until you get it sorted out. You risk overwriting the original backups.