[JJR512]

Just a quick guess, but maybe you tried to send to too many people at once. Try reducing the number of emails sent at one time. Once you set the initial options, and click on Preview Mailing, down at the bottom is a setting for Mails to send at once. By default, it is set to 500. Trying to generate and send 500 emails all at once may be a bit much for the particular server you're on, especially if your bulletin is larger than normal. Try setting it to maybe 100 users, and see if it works. It will take longer to complete the process, but at least you would be able to complete it.