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How to Fix SMTP Error 535-5.7.8: Username and Password Not Accepted

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You know how aggravating it can be if you have ever tried to send an email and ran across the “535-5.7.8 Username and Password not accepted” message. This mistake has to do with SMTP, the email-transporting Simple Mail Transfer Protocol used worldwide. This basically tells you via your email server that your login credentials cannot […]

RATS-NoPtr Blacklist: What Is It and How to Get Delisted

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Are your emails landing in spam? If so, you might be on an IP blacklist – and one of the culprits could be RATS-NoPtr. Blacklists are lists of IP addresses that have shown spam-like behavior or technical issues, which can block your emails from reaching recipients. RATS-NoPtr is a unique blacklist that flags IPs lacking […]

How to Fix SMTP Error 451 Temporary Local Problem in Emails

451 Temporary Local Problem (1)

Within the large field of digital communication, SMTP – Simple Mail Transfer Protocol – stands as a fundamental cornerstone. Fundamentally, SMTP is the protocol in charge of forwarding, receiving, and sending outgoing messages. Handling email delivery, it’s like the postal service of the internet. Emails too sometimes run against difficulties, much as a letter might […]

SMTP Error 554 5.4.6 – Too Many Hops: How to Fix It

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SMTP Error 554 5.4.6 “Too Many hops” is one of the most common errors faced by email administrators. It happens when an email message gets more “hops” than allowed while being passed along between mail servers.  To be more specific, this error happens because an email has already “hopped” through several servers. It can then […]