not able to send message to all members through our members e-mail account

We receive the following message that our members e-mail account cannot send the message because YOUR IP ADDRESS is listed on SpamCop:
members-xxx@toastmastersclubs.org (after MAIL FROM): 550 5.7.1 Mail from 205.169.121.111 refused because IP is on SpamCop.

I have replaced our club number in the above message with 'xxx'.

Thanks for your help,
Rhea Thompson
Webmaster
Westminster Communicators

The person sending the email needs to contact their email service as it is listed as a major source of smap.

smtp.quartz.synacor.com 205.169.121.111 is the offending mail service

www.spamcop.net/w3m?action=checkblock&ip=205.169.121.111

205.169.121.111 listed in bl.spamcop.net (127.0.0.2)

If there are no reports of ongoing objectionable email from this system it will be delisted automatically in approximately 17 hours.
Causes of listing

System has sent mail to SpamCop spam traps in the past week (spam traps are secret, no reports or evidence are provided by SpamCop)
SpamCop users have reported system as a source of spam about 20 times in the past week

Additional potential problems
(these factors do not directly result in spamcop listing)

Too many delisting requests were made. Next request might be allowed after 29.7 days

Because of the above problems, express-delisting is not available