The module keeps track of each time an email address is monitored as a bounce (unsuccessful send and is returned undeliverable). Enter the number of times any email address should be considered as a bounce before the module will stop sending to that address. E.g. if email@example.com bounces 5 times, and the number 5 is in the bounce count. The next time a campaign is sent to firstname.lastname@example.org, the module will remove that address before sending.
The module keeps count by using the bounce email settings to make a pop 3 connection to your mailbox and look for messages that have bounced. If you delete these messages from your account before the Bulk Emailer has time to process these, then the count will not be tracked.
This is one of the reasons we suggest sending from an address that is not your normal email account. This way you can leave the module operating and deleting messages that are bounce messages, and the process does not get confused with your normal email inbox.