Using telnet

[homers]

Hi
I am trying to use telnet to send an email to myself to see if it works.

Everything goes fine until I finish. It gives this error:

250 mail from IP soft failed sender ID check. Please ensure this IP is authorized to send mail on behalf of [hotmail.co.uk]

Why is this?
Thanks

[k1ll3rdr4g0n]

The SMTP server you are connecting to is probably checking the TXT record of the domain. And your IP isn't in that TXT record so the SMTP says "nope you can't send as this person because hotmail.co.uk says you are not allowed to send mail pretending to come from hotmail.co.uk". If you telneted into hotmail's SMTP server, I'm sure it would work fine.