Dear Client,

Gmail / G Suite started enforcing the use of SPF / DKIM / DMARC. This means that any email that is sent to gmail without those elements will be rejected with the message that you are seeing:

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550-5.7.1 This message does not have authentication information or fails to pass authentication checks. To best protect our users from spam, the message has been blocked. Please visit https://support.google.com/mail/answer/81126#authentication for more information
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If you follow the link in the rejection message then you will see the Authenticate section describing this: https://support.google.com/mail/answer/81126#authentication 

A) SPF
Sender Policy Framework. As default we apply: include:spf.mschosting.com that contains all Exabytes IP range no matter you signup Windows or Linux shared hosting plan.

You may perform a lookup on your domain SPF by using the following tools:
https://mxtoolbox.com/spf.aspx

If you are using a third party DNS but use Exabytes mail services, you may contact your current DNS services provider add the following line in the TXT record.

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v=spf1 include:spf.mschosting.com -all
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B) DKIM
DomainKeys Identified Mail. You may pronounced as “Di-Kim” if you wish to contact our support on this setup.

DKIM use a ‘private key’ to create signature on the contents of message then attached to it.It is like a secret code that you share among your family members or trusted friends.

When the recipient’s mail server receive the mail then it will ask sender to provide a public key to decrypt the supplied signature.

You can always check the current DKIM record of your domain by referring the following link
Ex: https://www.mail-tester.com/spf-dkim-check

C) DMARC
Domain-based Message Authentication, Reporting, and Conformance. You may pronounced as “Di-Mark”

It allow sender @ the company to publish a policy with the help of established SPF + DKIM then tell the recipient’s how to handle those unauthenticated mail via my domain DMARC policy.

Sample:
(V) Protocol version - DMARC1.
(P) - Policy - quarantine or reject.
(PCT) - Percentage of mail subject to filtering - 0 - 100.
(RUA) - Report URI of aggregated reports - Email Address.
(RUF) - Report URI of forensic reports - Email Address

Why applying the above is important to your DOMAIN?
Major email services provider start to enforce those checking from earlier spam score till a direct rejection at email communication, ex: Gmail.

If you need further information and clarification on the news or if you experience difficulties during this period, please contact us via helpdesk.

Best Regards,
Support Team

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Technical Support Department