But, please take the time to choose the correct forum for your posts. This forum is for questions on advanced Java. For more information, please read this.
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It sounds like the unsubscribe link would need to contain the mail address, and then the PHP page would take parameter and do with it whatever needs doing.
That's insecure, though, because people could unsubscribe anybody from the list who's address they can guess, just by manipulating the link.
The safer way to do this would be to embed something in the URL that's cryptologically secure (like the encrypted address).
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