Email refusal from Windows live hotmail

Hi, My email is being returned from Windows live hotmail. The recipient has not changed anything on his acct but now he can't receive from my address. I use rocketmail (a yahoo acct). I have attached below the notice I see when it bounces back. Does anyone know how to remedy this so I don't have to make a new email add just for my Windows live hotmail friends?
Thanks! Tess
Remote host said: 550 SC-001 Mail rejected by Windows Live Hotmail for policy reasons. Reasons for rejection may be related to content with spam-like characteristics or IP/domain reputation problems. If you are not an email/network admin please contact your E-mail/Internet

Most likely either the email host/domain you are using (i.e. hotmail.com, gmail.com, yahoo.com, whatever.com, etc) or your ISP range has been listed by Windows Live Hotmail as spammers or some other blacklist user. The only real solution is to contact Hotmail tech support and inform them that your domain is being rejected.

Here's a link generally discussing the problem. You *may* have a much more specific problem that can be fixed, but based on the info you've given us, this is the most likely cause.

Good luck!

http://www.eggheadcafe.com/software/...id-550-sc.aspx

Thanks Greyhound, I'll contact them!
Tess