Manual Telnet Test
There are a number of ways to manually perform a mail transaction through telnet. The following procedure should work under a variety of operating systems, including Windows, UNIX and Linux.
This section describes how to manually perform a mail transaction through telnet. If you do not receive the replies shown, copy the entire transaction and save it so that you can report the error you received. In order for this test to be useful, it must be run from directly from the mail server.
Generally OK codes start with 2nn and Error codes start with 5nn. An example of an error code would be if you connect to us and receive 554 RTR:SC .... A 5nn error code could indicate a number of problems, for example a syntax error or AOL systems blocking your incoming connections due to lack of RDNS or excessive user complaints.
To manually perform a mail transaction through telnet, perform the following steps:
The transaction should appear similar to the following: