We just installed a new sonicwall Firewall and all is working well. Problem is... we have some pop3 clients out there and a few of them are having this problem. It seems that the connection to the server is terminated before it can tell it to delete the messages received off the server. They are using outlook express and all the proper settings are in place. It is set to not save messages on the server. They can receive new messages but the same ones keep piling in.