Select Page

Author: Cary Sun

Cary Sun has a wealth of knowledge and expertise in data center and deployment solutions. As a Principal Consultant, he likely works closely with clients to help them design, implement, and manage their data center infrastructure and deployment strategies. With his background in data center solutions, Cary Sun may have experience in server and storage virtualization, network design and optimization, backup and disaster recovery planning, and security and compliance management. He holds CISCO CERTIFIED INTERNETWORK EXPERT (CCIE No.4531) from 1999. Cary is also a Microsoft Most Valuable Professional (MVP), Microsoft Azure MVP, Veeam Vanguard and Cisco Champion. He is a published author with several titles, including blogs on, and the author of many books. Cary is a very active blogger at and is permanently available online for questions from the community. His passion for technology is contagious, improving everyone around him at what they do. Blog site: Web site: Blog site: Twitter: @SifuSun in: Amazon Author:

Total Posts: 358

Microsoft Defender for Office 365-Find the Domain Name of the Trusted ARC Sealers from the Message Header

An email message internet header is a metadata set containing information about the sender, recipient, routing, and delivery of an email. It can help you find the domain name of the trusted ARC sealers. The domain name must match the domain specified in the d value of the ARC-Seal and ARC-Message-Signature headers in affected messages.

Read More

Microsoft Defender for Office 365-Configure trusted ARC sealers email authentication for Microsoft 365 Custom domains

Authenticated Received Chain (ARC) is a mechanism used in email authentication protocols to address the issues of message forwarding and intermediary handling of emails. It is designed to improve the reliability and security of email authentication systems like SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail).

Read More

Microsoft Defender for Office 365 – Configure DMARC email authentication for Microsoft 365 Custom Domains

Domain-based Message Authentication, Reporting, and Conformance (DMARC) builds upon SPF and DKIM to give domain owners greater control over how recipient servers handle their email messages. With DMARC, domain owners can specify policies instructing recipient servers on how to handle emails that fail SPF or DKIM checks. DMARC also enables domain owners to receive reports on email authentication results, allowing them to monitor and improve their email security posture.

Read More