When you have a problem connecting to your ISP’s SMTP server from a device such as a Copy machine , or scanner, diagnosis is often difficicult. The same account may connect using an email client. You need an alternate method to view the responses from the SMTP server in real time. Telnet provides a solution. Using telnet you can authenticate the username & password & send an email once authenticated.
First thing to note is that , the request for authenticaton & your response are conducted using base64 encoding. You can use an online source to perform this conversion for you. This is one such resource. http://www.motobit.com/util/base64-decoder-encoder.asp
Using this resource I converted the following to base64 encoding
| username/email address | sender@sender.com | c2VuZGVyQHNlbmRlci5jb20= |
| password | 123abc | MTIzYWJj |
Note:
1. Telnet client needs to be installed , it is no longer installed by default.
2. CASE is very important
Open a telnet session to the mail server , you need to specify the SMTP port , even if it is at the default port of 25.
C:>telnet smtp.domainname.com 25
The rest of it is in the telnet window
The server typically responds with a 220 message
Type EHLO reciever.com
Type AUTH LOGIN
The server should respond 334 VXNlcm5hbWU6
Type the username c2VuZGVyQHNlbmRlci5jb20=
The server will respond 334 UGFzc3dvcmQ6
Type the password MTIzYWJj
If all goes well , the server will respond 235 Authentication succeeded
You next need to send a message.
Type MAIL FROM: <sender@sender.com>
RCPT TO: <reciever@reciever.com>
DATA
FROM: <sender@sender.com>
Type any text you want , Please call me
Type <Enter>
Type .
Type <Enter>
Note: the last three are ENTER , PERIOD , ENTER on 3 lines.
Type quit to exit