Email one time and one time only

Jo-Ann Tan

One of our fundraisers is providing us access to their email list and we can use it one time only to ask people if they will sign-up for our email list.  How do I load that list into Convio, send one email out, then flag everyone who does not opt-in as as "does not accept email".  I'm not sure suire how to set up the right sequence of events.  Has anyone done this before? Any advice? Thanks.