"from" address automatically filling in?

New to Campaignmonitor, but so far love it. Can't find this answer in the forums. Emailed tech support also.

Client wishes to have a person's name in the "from" box that's different than the email address and reply to address, which will be hers. When I set it up that way and test, I receive the mail and it's showing her name in the "from" box, rather than the name I entered in Campaignmonitor. Tested it several times. If I put bogus emails in the "from" and "reply" and test it, the "from" name is correct.

My questions, (1) is my mail client (Entourage) overwriting the name in the "from" box because is recognizes my client's email address in the "reply to" field from my address book? (2) Will it do that for everyone who has my clients' email address in their address book and (3) Any way to prevent it?

Clear as mud?

Thanks, Dan

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