Secure Receipt Error

There were problems verifying this secure receipt.

Outlook Express was unable to find the original message that requested this receipt.  The Original message is required to verify a secure receipt.  The following are some possible reasons the original message could not be found:

• The original message was is not in your Sent Items folder.
  
• You have deleted the message from your Sent Items folder.
  
• If you are using an IMAP account, it may be configured to save sent messages on the server.   Please synchronize all messages in your sent items folder.  To prevent this problem in the future, you can configure your account to use your local Sent Items folder instead of one located on the server.