Mail forgets, forgets, forgets...

Problems such as yours are sometimes caused by files that should belong to you but are locked or have wrong permissions. This procedure will check for such files. It makes no changes and therefore will not, in itself, solve your problem.

First, empty the Trash.

Triple-click the line below to select it, then copy the selected text to the Clipboard (command-C):

find . $TMPDIR.. \( -flags +sappnd,schg,uappnd,uchg -o ! -user $UID -o ! -perm -600 -o -acl \) 2> /dev/null | wc -l

Launch the Terminal application in any of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

☞ Open LaunchPad. Click Utilities, then Terminal in the icon grid.

Paste (command-V) into the Terminal window. The command may take a noticeable amount of time to run. Wait for a new line ending in a dollar sign (“$”) to appear.

The output of this command, on a line directly below what you entered, will be a number such as "75." Please post it in a reply.

Back up all data.

This procedure will unlock all your user files (not system files) and reset their ownership and access-control lists to the default. If you've set special values for those attributes on any of your files, they will be reverted. In that case, either stop here, or be prepared to recreate the settings if necessary. Do so only after verifying that those settings didn't cause the problem. If none of this is meaningful to you, you don't need to worry about it.

Step 1

If you have more than one user account, and the one in question is not an administrator account, then temporarily promote it to administrator status in the Users & Groups preference pane. You can demote it back to standard status when this step has been completed.

Triple-click the following line to select it. Copy the selected text to the Clipboard (command-C):

sudo chflags -R nouchg,nouappnd ~ $TMPDIR.. ; sudo chown -R $UID:20 ~ $_ ; chmod -R -N ~ $_ 2> /dev/null

Launch the Terminal application in any of the following ways:

☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)

☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.

☞ Open LaunchPad. Click Utilities, then Terminal in the icon grid.

Paste into the Terminal window (command-V). You'll be prompted for your login password, which won't be displayed when you type it. You may get a one-time warning not to screw up. If you don’t have a login password, you’ll need to set one before you can run the command.

The command will take a noticeable amount of time to run. Wait for a new line ending in a dollar sign (“$”) to appear, then quit Terminal.

Step 2

Boot into Recovery by holding down the key combination command-R at startup. Release the keys when you see a gray screen with a spinning dial.

When the OS X Utilities screen appears, select

Utilities ▹ Terminal

from the menu bar. A Terminal window will open.

In the Terminal window, type this:

resetpassword

That's one word, all lower case, with no spaces. Then press return. A Reset Password window will open. You’renot going to reset a password.

Select your boot volume ("Macintosh HD," unless you gave it a different name) if not already selected.

Select your username from the menu labeled Select the user account if not already selected.

Under Reset Home Directory Permissions and ACLs, click the Reset button.

Select

 ▹ Restart

from the menu bar.

The following is an exception to the rule that you should never make any changes to backup data. I've tested this procedure in OS X 10.8 only. I don't know whether it works in earlier versions of OS X. Use this procedure only for files that were backed up from your home folder, or a folder on another volume created by you, and would normally be writable by you. Do not touch backups of system or application files.

In the Finder (not in the time-travel view), navigate to the backup volume, then to the folder named "Backups.backupdb", and then to the snapshot you want to restore from. The snapshots are folders labeled with the date when they were created. Inside each of those folders is a file hierarchy like the one on the volume that was backed up. Descend through the hierarchy until you come to a folder named "Users," and inside that, a folder with your user name. The procedure will be different if you're trying to restore files on another volume.

Select the folder and open the Info dialog (command-I). Click the padlock icon in the lower right corner of the window and authenticate. In the Sharing & Permissions section, give your account Read & Write access. You may have to close the window and repeat this step in order for the change to show up. Then click the gear icon and select Apply to Enclosed Items from the popup menu.

Try the restore operation again, in the time-travel interface.

You will never get back to normal if you don't fix the permissions of your home folder. If you restore bad permissions from Time Machine after doing that, the permissions will be wrong again.

If I understand your report, you were unable to restore some files from backups. That's because Time Machine won't let you access files you don't have read permission for. I explained how to correct that. I suggest you take those steps, then restore. After that you may need to take the steps to fix your home folder again. When everything is back to normal, the number you get from the first shell command should be around 85, maybe less or a little more.

As I wrote above, you must be an administrator to carry out that procedure.

Yes.