Is rb4.com valid?

Domain: rb4.com

Valid: Yes, but should be blocked

This domain is valid and should be able to receive e-mail.

Tested MX: rb4.com (44.227.76.166)

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No MX-pointer in DNS record. Using domain: rb4.com

Block: Yes

You should block this domain for signups/registrations.

Disposable: No

This does not look like a temporary/disposable e-mail domain.

Raw API reason:

Anomalies detected

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