Are you on your own server.....

I think it has to do wtih some hosts not allowing lots of email addresses relayed in the BCC field.

The field that you fill in, when you send your email gets put in the "TO:" part of the email headers.... the email addresses of the users get put in the BCC field.

I would ask your host if they allow mail in the BCC field like that. You are basically BCCing 50 people at a time when you mass email from threads.

Or email error logs might offer some clues. <img border="0" title="" alt="[Wink]" src="images/icons/wink.gif" />

Josh
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