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SUMail is an option for organizations, clubs and groups that want to email their members or constituents when the targeted audience is small. However, there are limits to the number of recipients you can send to in SUMail. If you are receiving an error when sending to many recipients in SUMail, you may be exceeding that limit. For cases where you want to email larger numbers of recipients, we recommend you look at either Microsoft 365 groups or Listserv Lists (see documentation below).
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