On exchange 2007 I receive the following error:
One or more (1) e-mail messages in the POP3 mailbox account 'email@example.com on the POP3 server 'mail.domain.com' have invalid header fields. Because of this, the messages cannot be delivered to the Exchange Server mailbox 'firstname.lastname@example.org 'in Windows Small Business Server. The messages are still on the POP3 server. To resolve this issue, connect to the POP3 mailbox account, and then manually retrieve or delete the messages.
Can I adjust the exchange to download all the email message so I do not bother to delete this email messages. This is happening almost every week, and until I delete the emails with invalid headers, the user does not receives his emails.