Okay experts - Exchange 5.5 organization all exchange servers are Win2K OS I have a user sending a 10 MB attachment from one site to another. The message of course is sent over the X400 connection... I have verified that I have no message size limit restrictions on the X400 connector. The following bounce back occurs: The content length of the message is too long for the recipient to take delivery The MTS-ID of the original message is: c=US;a= ;p=GlobalKNet;l=NC10S106-040312164526Z-76891 MSEXCH:MSExchangeMTA:NEST:TX12S001 What is going on? I have not had problems with this before, and the recipient mailboxes have plenty of room to receive the message. We can send from Server to Server in the same site with no problems. Thanks for any info. chris