my LAN is protected by an ISA server. However exchange server is installed inside the LAN, some users are using external mails servers like yahoo. to check the mail using outlook inside the LAN and outside the LAN is ok but nobody can check mails from a external servers behind ISA server and the error message is that: Your server has unexpectedly terminated the connection .. error number:0x800CCC0F I defined a protocol rule to allow pop3 and pop3 server for any request at any time , still the problem is there. I would appreciate any help ... Alan _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com