I am having issues with 4 Blackberry's that were working fine but now I am getting errors only when replying and forwarding emails with attachments. Receiving and sending emails are no problem. We are using BIS to SBS 2003 Server. Messages have Red X and error message is always "Message included an invalid address". All 4 Blackberry's are different models and some are on Verizon and others on Sprint network. Any help would be great!