MailboxValidator service allows you to check email address validity to reduce the number of undelivered mails. Inevitably, this will improve your email delivery success rate and reduce your bad email reputation which may result in your email address being blacklisted.
Role-based emails are emails like email@example.com, firstname.lastname@example.org or email@example.com which may turn out to be a mailing list with multiple recipients. These email addresses are commonly rejected by email sending providers due to the fact that not everyone on the recipient list may have opted to receive your emails.
MailboxValidator connects to the SMTP servers in real-time for validation purposes. Sometimes, the mail servers are very busy and takes a while to respond to commands. Hence, the longer time taken to process the email validation.
The credits will be summed up with a new expiry date based on the latest purchase. For example, suppose you have 433 credits which will be expired on 24-Sep-2013, and you buy another 500 queries plan on 22-Sep-2013. You new credits will now be 933 with the new expiry date on 21-Oct-2013.
MailboxValidator will automatically replenish your credits by renewing your subscribed plan upon running out of credits. This is to ensure that your API works at all times without any interruption due to insufficient credits. Only applies to paid API plan.
You will need to obtain an invitation code from a paid API user who has subscribed to the API-15 plan or higher. The paid user can see the invitation codes in his account after login under the "INVITE API-FREE+" section. During the sign up process for the API-FREE+ plan, you will need to key in the invitation code.