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This plugin prevents people from registering with disposable email addresses (dea) like the ones provided by mailinator (also known as throw-away email, one-time email). It protects your most important asset, your registered user base, by preventing contamination by fake accounts. This plugin working principle is similar to spam blacklists.
It hooks in the wordpress function is_email() so it will extend the known email validation of wordpress to detect dea domains.
The plugin itself does not contain a list of domains to block. Instead of local maintenance the plugin uses the service of http://www.block-disposable-email.com. This is a very accurate free service for up to 200 queries a month. For huge sites several commercial plans are available.
Please see the FAQ section for some more information.

Block Disposable Email

This plugin detects one-time email addresses (disposable email, trashmail, mailinator, 10minutemail) and helps to keep your userbase and comments clea …

Sajjad Hossain Sagor

Block Spammy Disposable/Temporary Emails To Submit On Ninja Forms. Filtering Spammy Emails Will Increase Your Real Subscriber List.
<h4>Features:</h4>
<ul>
<li>Easy As 123, Just Plug & Play</li>
<li>Toggle To Enable/Disable For Individual Form</li>
<li>Translation Ready</li>
<li>Set Disposable/Temporary Emails Found Message (Default Message Provided)</li>
</ul>
Daily Hundreds of people submit emails to get free stuff but most of the time they use spammy disposable/temporary emails to get them… but now you can prevent that from happening. You can use this plugin to block/prevent disposable emails like 10MinuteMail and GuerrillaMail from submission on any Ninja Forms form.
Credits 
– https://github.com/andreis/disposable

Disposable Email Blocker – Ninja Forms

Block Disposable/Temporary Spam Emails On Any Ninja Forms From Submitting.

Block Disposable Email vs Disposable Email Blocker – Ninja Forms