Search in Mail (Mountain Lion) doesn't work

Question

I have a new MacBook Air running 10.8.5, and migrated a new user from an older Mac using Migration Assistant. Everything is fine but the search function doesn't return any results in Mail. I have rebuilt the mailboxes, and also re-indexed spotlight by adding then deleting the disk. All the posts about this subject on the forums are quite old...has this problem been solved yet?
(Note that when I do the search using Spotlight, the emails do show up. It's when I use the search function within Mail that I get no results.)
Thanks for any help.
<Subject Edited by Host>

Answer 1

Please follow these directions to delete the Mail "sandbox" folder.
Back up all data.
Triple-click anywhere in the line below on this page to select it:
~/Library/Containers/com.apple.mail
Right-click or control-click the highlighted line and select
Services ▹ Reveal
from the contextual menu.* A Finder window should open with a folder named "com.apple.mail" selected. If it does, move the selected folder — not just its contents — to the Desktop. Leave the Finder window open for now.
Log out and log back in. Launch Mail and test. If the problem is resolved, you may have to recreate some of your Mail settings. You can then delete the folder you moved and close the Finder window. If you still have the problem, quit Mail again and put the folder back where it was, overwriting the one that may have been created in its place. Post your results.
Caution: If you change any of the contents of the sandbox, but leave the folder itself in place, Mail may crash or not launch at all. Deleting the whole sandbox will cause it to be rebuilt automatically.
*If you don't see the contextual menu item, copy the selected text to the Clipboard by pressing the key combinationcommand-C. In the Finder, select
Go ▹ Go to Folder...
from the menu bar, paste into the box that opens (command-V). You won't see what you pasted because a line break is included. Press return.