1. open command prompt (start-> all programs -> Accesories -> command prompt)

2. copy & paste below 5 lines, one by one
   

telnet smtp.icc-computer.com
ehlo smtp.icc-computer.com
auth login
bGVp
cGFzc3dvcmQ=


3. close the command prompt after finishing the test



Notes: 

1) you'll see below output if successful. can you see it?
2) "bGVp" and "cGFzc3dvcmQ=" is the user name / password for the test, 
   it's a base64 encoding of user name / password and created by:
   
   perl -MMIME::Base64 -e 'print encode_base64("username");'
   perl -MMIME::Base64 -e 'print encode_base64("password");'

  
--- the output if successful---

220 smtp.icc-computer.com ESMTP Postfix (Ubuntu)
ehlo smtp.icc-computer.com
250-smtp.icc-computer.com
250-PIPELINING
250-SIZE 10240000
250-VRFY
250-ETRN
250-STARTTLS
250-AUTH PLAIN LOGIN
250-AUTH=PLAIN LOGIN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
auth login
334 VXNlcm5hbWU6
bGVp
334 UGFzc3dvcmQ6
cGFzc3dvcmQ=
235 2.7.0 Authentication successful
--------------------------------------