by quickemailverification on WordPress.org
The QuickEmailVerification email verification plugin to avoid fake, bad and nonexistent emails.

Setting page for QuickEmailVerification Email Validator. Here you can add your QuickEmailVerification API Key and select which email addresses you want to exclude from Role, Disposable and Accept All.
An email verification plugin by QuickEmailVerification enables you to validate and verify the email address existence in real time, before you actually send them an email. Its unique email verification system is composed of multiple different validations starting from syntax checking to the end users’ mailbox existence checking. It not only detects invalid email addresses but also detects many other types of poor email addresses which could negatively impact the email deliverability and harm your sender reputation.
This plugin need a QuickEmailVerification API key to verify. You can get it from API settings page of QuickEmailVerification service.
This plugin works either with “is_email()” function or with any other supported form plugins. So if any supported form plugin is enabled, “is_email()” hook will automatically be disabled.
To know more about email verification results, please have a look at the QuickEmailVerification knowledge base.