Category Archives: Small Business Server 2008

Error 217: Invalid header fields (POP3 Connector)

Problem The POP3 Connector of the Small Business Server 2008 always showing the following error message in eventlogs and the read confirmations are not received by the originating sender. Event ID 217 One or more (x) E-Mail Messages in the POP3 Mailbox account ‘’ on the POP3 Server ‘’ have invalid fields. Because of this, the Messages are still on… Read more »