There may be depending upon who your ISP is. Found out that on my particular
ISP there is a limit of 25 recipients distributed between the To: CC: and
BCC: fields. They are trying to locate a commercial server where there isn't
a limit on the number of recipients. There is a limit of 10 recipients in the
To: field.
So if you are experiencing difficulty with this, you may want to check into
the different ISPs. But until I got the official information from Microsoft
that this was NOT determined by Outlook, I kept getting bounced between the
anti-virus people and the ISP.
Hope this helped.