Can anyone with some clue help with sorting this out?

I've tired following the link but I just don't understand what I'm not doing right.

My mail server got compromised and has since been fixed but I'm still having problems sending mail to gmail.

                   The mail system

<Laurajmcintosh@gmail.com>: host gmail-smtp-in.l.google.com[173.194.203.27]
    said: 550-5.7.1 [182.54.234.40      12] Our system has detected that this
    message is 550-5.7.1 likely unsolicited mail. To reduce the amount of spam
    sent to Gmail, 550-5.7.1 this message has been blocked. Please visit
    550-5.7.1  https://support.google.com/mail/?p=UnsolicitedMessageError 550
    5.7.1  for more information. c10-v6si12022767plr.398 - gsmtp (in reply to
    end of DATA command)

-- 
Don Gould
31 Acheson Ave
Mairehau
Christchurch, New Zealand
Ph: + 64 3 348 7235
Ph: 0800 00 15 92 
Mobile: + 64 21 114 0699
Ph: +61 3 9111 1821 (Melb)
www.yournet.co.nz
skype:  don.gould.nz