How to Configure Outlook Hierarchical Address Book to Sync With Org Chart

If you manage an Exchange or Microsoft 365 environment, you may need to help users quickly find colleagues by their position in the company structure. The Outlook Hierarchical Address Book, or HAB, displays recipients in an organizational tree based on the company’s management hierarchy. This feature replaces the flat global address list with a view … Read more

Outlook Cached Address Book NK2 to RoamCache Migration: How to Force

When you upgrade Outlook from an older version that uses a .nk2 file for nickname autocomplete to a newer version that uses RoamCache, the migration of your cached address book entries may not happen automatically. This can leave you without your frequently used email addresses and contact suggestions. The migration is triggered by specific Outlook … Read more

Outlook Folder Subscription Limit Exceeded: How to Reduce Subscribed Set

When you see the error “Folder Subscription Limit Exceeded” in Outlook, it means you have more folders subscribed than your account allows. This typically happens in Microsoft 365 or Exchange Online accounts where administrators set a maximum of 500 subscribed folders per mailbox. The error prevents you from seeing new messages in some folders or … Read more

How to Apply Sensitivity Labels to Outlook Email With Microsoft Purview

Sensitivity labels from Microsoft Purview let you classify and protect email content directly in Outlook. These labels apply encryption, watermarking, and header markings to prevent data leaks. You might need to apply a label because your organization requires it for compliance or because you want to control who can read or forward an email. This … Read more

Outlook S/MIME Email Signing: How to Install a Personal Certificate

When you send an email in Outlook, recipients cannot always verify that the message came from you and has not been altered. S/MIME (Secure/Multipurpose Internet Mail Extensions) solves this by letting you digitally sign your emails using a personal certificate. Without a properly installed certificate, Outlook cannot apply the signature. This article explains what an … Read more

How to Encrypt an Outlook Email With Office Message Encryption (OME)

You need to send sensitive information such as financial data, legal documents, or personal health details through email. Outlook includes a built-in feature called Office Message Encryption or OME that protects your message content from unauthorized access. This article explains what OME does and the exact steps to encrypt an email in Outlook for Windows, … Read more