what email program are you using and what is the exact error that you get? does it refuse to send to the group or do you get bounce back emails ?
if you send it to the same group as a regular cc it goes through ?
there is actually a contact on the original page that you sent me if you click on it you get a form to fill out where you can ask why it is being flagged as spam.
it may come down to something as silly as your ip changed to one that is flagged as previously used for spam. You can test that by trying to send from another location. or you can call your isp and request that they change your IP address because it is getting flagged as spam.
otherwise the solution is to load the google groups app and use that to send the emails.
well i hope that you will give me a good rating.
then you would need to email***@******.*** to tell them that you dont want a subscription