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Microsoft Entra (Identity)
- Adding a named location without breaking Conditional Access
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Exchange & Outlook
Email, calendars, mail flow, and Outlook clients. 27 guides in this topic.
Recently reviewed
- Adding a new domain to Microsoft 365 without email downtimeHow to add an email domain to Microsoft 365 without downtime: verification, accepted-domain type, SPF, DKIM, DMARC before MX, and the mail-flow traps.
- BIMI and brand indicators in emailBIMI shows your brand logo next to email from your domain in supported clients. Here's the setup and the prerequisites.
- Distribution lists vs Microsoft 365 GroupsHow DLs, mail-enabled security groups, and Microsoft 365 Groups differ — and when to use each.
- DMARC rollout from p=none to p=rejectReviewed 2026-09-06How to roll out DMARC enforcement progressively — the journey from monitoring to enforced anti-spoofing.
- Exchange hybrid deploymentReviewed 2026-08-31How hybrid Exchange works — connecting on-prem Exchange Server with Exchange Online, what the wizard actually does, and the path off the last server.
- Exchange Online anti-spam and anti-phishingThe layered defences Exchange Online uses against spam, malware, and phishing — and how to tune them.
- Exchange Online archiving and litigation holdHow Exchange Online keeps mail beyond the primary mailbox — archive mailboxes, retention, and legal hold.
- Exchange Online mail flow and connectorsReviewed 2026-09-05How mail moves into and out of Exchange Online — connectors, transport rules, and hybrid routing.
- Exchange Online resource mailboxesHow room and equipment mailboxes work — provisioning, booking, and admin pitfalls.
- Exchange transport rule examplesReal-world transport rule patterns — external-sender warnings, encryption triggers, blocking, and compliance scenarios.
- How to convert a user mailbox to a shared mailboxHow-toHow to convert a user mailbox to a shared mailbox in Exchange Online, when it's the right leaver move, the 50 GB and hold rules, and removing the licence.
- How to put a mailbox on litigation holdHow-toHow to put a mailbox on litigation hold in Exchange Online: licence check, enabling the hold with a duration, what it preserves, and releasing it correctly.
- How to set up DKIM for a custom domain in Microsoft 365How-toHow to set up DKIM signing for a custom domain in Microsoft 365: the two CNAME records, enabling it in Defender, key rotation, and checking headers.
- Managing Outlook signatures at scaleHow to manage email signatures in Outlook — cloud signatures, transport rules, and third-party tools.
- Migrating a shared mailbox to a distribution group, or backHow to move an address from a shared mailbox to a distribution group, or back, without dropping mail — what happens to history, and when a Group is better.
- New Outlook vs classic Outlook on WindowsReviewed 2026-08-31New Outlook vs classic Outlook on Windows: what actually changes, what still doesn't work, and how to run the migration without a user revolt.
- Office 365 Message EncryptionOME is Microsoft's email encryption service — what it does, how to enable it, and what it looks like for recipients.
- Office 365 Message Encryption deep diveHow OME works under the hood — encryption flow, branding, custom templates, and the recipient experience.
- Outlook cached mode and OST filesHow classic Outlook caches mailbox data locally — what an OST file is, when to use cached mode, and the modern alternatives.
- Outlook calendar delegationThe three ways to share a calendar in Outlook — delegate access, share permissions, and shared calendars.
- Outlook Focused Inbox and the legacy Clutter folderHow Focused Inbox separates important mail from the rest, and what happened to its predecessor Clutter.
- Outlook mobile policies and app protectionHow to govern Outlook mobile on iOS and Android — app protection policies, security settings, and feature controls.
- Outlook rules and automationClient-side rules, server-side rules, and Power Automate — the three ways to automate email handling in Microsoft 365.
- Proxy addresses and email aliases in Exchange OnlineHow Exchange Online decides which addresses a mailbox answers to: proxy addresses, primary SMTP, UPN vs email, sending from aliases, and hybrid gotchas.
- Retiring on-prem Exchange after a full migrationWhat must be true before the last Exchange server can go: recipient management, relay, public folders, management-tools-only, and the removal sequence.
- Shared mailboxes explainedShared mailboxes are mailboxes multiple people can monitor. Here's how they differ from groups, distribution lists, and personal mailboxes.
- What is Exchange Online?Reviewed 2026-08-27What Exchange Online is: Microsoft 365's cloud email and calendaring, how it fits the platform, the security and compliance layers, and running it well.
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