Question : TRANSACTION FAILED in Outlook 2007 email

My outlook has been working ok, now all of the sudden no emails can be sent (only if I send myself).  Each email I send returns the following:

Your message did not reach some or all of the intended recipients.

      Subject:      RE:
      Sent:      12/11/2009 6:40 PM

The following recipient(s) cannot be reached:

      'Ceasare' on 12/11/2009 6:40 PM
            554 5.5.0 E7.10 TRANSACTION FAILED

      '[email protected]' on 12/11/2009 6:40 PM
            554 5.5.0 E7.10 TRANSACTION FAILED

      '[email protected]' on 12/11/2009 6:40 PM
            554 5.5.0 E7.10 TRANSACTION FAILED

Answer : TRANSACTION FAILED in Outlook 2007 email

From everything I have read on this error, this problem is related to AOL and not Outlook. You can try this fix here:
http://www.eggheadcafe.com/software/aspnet/28530352/-received-554-transact.aspx