Infrastructure
Oct 7, 2026·~3 min read
How to Read Gmail Postmaster Tools
Read Gmail Postmaster Tools: verify your domain, domain reputation, spam rate near 0.3%, and authentication charts versus what headers show on a single message.
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ZeroHook Blog
Fixes, not fluff. DNS security and compliance guides for IT managers who already know the acronyms.
Infrastructure
Oct 7, 2026·~3 min read
How to View Email Headers in Gmail
View email headers in Gmail, Outlook, and Apple Mail: open Show original, find Authentication-Results, and read spf=, dkim=, and dmarc= without guessing.
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DKIM
Oct 4, 2026·~3 min read
Google Workspace DKIM Setup (2026)
Turn on DKIM in Google Admin, publish the google._domainkey record at your DNS host, and verify dkim=pass in Gmail headers before DMARC alignment breaks bulk sender rules.
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DMARC
Oct 4, 2026·~3 min read
DMARC for Google Workspace
Publish DMARC for Google Workspace: starter TXT at _dmarc, rua reporting, alignment with google DKIM, and when to leave p=none before quarantine.
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Infrastructure
Oct 4, 2026·~4 min read
What Is an MX Record?
What is an MX record? Learn how mail exchanger priority works, why SPF does not replace MX, and three ways to verify routing before receipts and alerts stop arriving.
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SPF
Oct 4, 2026·~3 min read
Google Workspace SPF Record Mistakes
Google Workspace SPF setup: the correct include:_spf.google.com line, Mailchimp and HubSpot add-ons, and the migration mistakes that leave DMARC failing while Admin looks green.
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Compliance
Jun 29, 2026·~7 min read
SOC2 CC6.6 DNS Monitoring Evidence
SOC2 CC6.6 DNS monitoring evidence for Type II: enforced DMARC, MTA-STS, change detection, and tamper-proof logs auditors accept when Excel exports fail.
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