A Suppression List is a list of suppressed e-mail addresses used by e-mail senders to comply with the CAN-SPAM Act of 2003. CAN-SPAM requires that senders of commercial emails provide a functioning opt-out mechanism by which email recipients can unsubscribe their email address from future email messages. The unsubscribed email addresses are placed into a "suppression list" which is used to "suppress" future email messages to that email address.
Go To: Communities >> Members >> Make Members Inactive
Go to: Login to community >> My account >> Unsubscribe
Example
https://qpcommunities.questionpro.com/a/globalSuppression.doIn the example above, if /a/globalSuppression.do is appended to your community url, and the url is visited, users can add their email address to the Unsubscribe list there.