Applescript for mail error can't get message id

Question

I have an applescript (found on internet) for Mail 4.5 that deletes messages in "on my mac" mailbox "Deleted Inbox" that are older than 120 days. The script runs from an iCal daily event. I drag messages from Inbox to "Deleted Inbox" when I don't want the message in Inbox, but I want to save the message for 120 days before deleting it. The script sometimes runs successfully, and sometimes gives error "Mail got an error: Can't get message id xxx of mailbox "Deleted Inbox"". Then in Mail, I "Mailbox / Rebuild" that mailbox, and run the script manually without error. How can I avoid that error? The script is essentially:
tell application "Mail"
          set OldStuff to every message of mailbox TheBox where date received of it < OldDate
          repeat with ThisMessage in OldStuff
    delete ThisMessage
          end repeat
end tell
Thanks for any help.
Ken

Answer 1

How can I avoid that error?
I don't actually know how you can avoid that error. However, maybe you can use a workaround and have the script rebuild the mailboxes automatically when such an error occurs. Try the following code:
tell application "Mail"
  try
    set OldStuff to every message of mailbox TheBox where date received of it < OldDate
  on error
    activate
    tell application "System Events" to click menu item "Rebuild" of menu 1 of menu bar item "Mailbox" of menu bar 1 of process "Mail"
    delay 1 -- adjust if necessary
    set OldStuff to every message of mailbox TheBox where date received of it < OldDate
  end try
  repeat with ThisMessage in OldStuff
    delete ThisMessage
  end repeat
end tell
Since the above script uses GUI Scripting, you must enable the Accessibility Frameworks by clicking the checkbox labeled "Enable access for assistive devices" in the Universal Access System Preference pane.
Message was edited by: Pierre L.