Thank you very much warwickp!
Your troubleshooting steps worked for me!
Hi there,
I had to go a long, long way to get you this, so I really hope iot’s going to help: http://www.vincentprat.info/dev/?page_id=3/email-users-support/email-users-316-and-wp-27
Well, I needed it back too, the button went with the upgrade to wp 2.8.1
And I think there are access level issues too.
Let me know how it goes!