Security Guides

Plain-English advice for using online tools without exposing sensitive data.

All Security guides

Security August 15, 2026

168 Domains Have SPF Records That Look Fine and Silently Don't Work

We expanded the SPF records of the Tranco top 10,000 domains. 2.2% exceed the RFC 7208 ten-lookup limit once includes are followed, including 54 running p=reject on an SPF record receivers cannot finish evaluating.

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Security June 24, 2026

PDF Password Protection Before Sharing: What It Can and Cannot Do

A realistic guide to password-protecting PDFs, including when it helps and when teams need stronger safeguards.

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Security June 22, 2026

A Security Checklist for Using Online File Tools

Use this practical checklist before uploading files to online tools for conversion, compression, merging, or processing.

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