I'm glad to your nice support.Thanks.
Then,I have a question.
I use your e-Newsletter plugin and Membership plugin together.
In my test case,When I get a mail from plugin,and click "Unsubscribe Instantly.",Surely Unsubscribed.
Then,Next,I tested subscribe again by admin user like follows.
But I can't find out
'Users > All Users, click the Edit link for the user. Scroll down to the bottom and set "Receive admin emails"'
If Administrator subscribe user again,What do I do?
I watch my db table called
wp_enewsletter_members and find a column which Unsubscribe user's row's 'unsubscribe_code' is empty.
Is this related?