Sender Policy Framework

FAQ/Underscore in DNS

Whoa, that's an underscore in spf. I thought you could only have letters, numbers, and dashes in domain names, no underscores?

Underscores are okay in domainnames, just not in hostnames.

This is not really SPF-specific, please see DNS/Underscore for more information.

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Sender Policy Framework

FAQ/Underscore in DNS

Whoa, that's an underscore in spf. I thought you could only have letters, numbers, and dashes in domain names, no underscores?

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