Manage, secure, and optimize Active Directory with guides on authentication, domain services, user management, and enterprise security best practices.
Home » Microsoft Entra » Troubleshoot Microsoft Entra Connect Installation Issues Last Updated: July 2026 Answer Capsule: Most Microsoft Entra Connect installation problems trace back to three things: a domain controller that shouldn’t be hosting the sync engine, a SQL Server running out of headroom, or an unverified UPN suffix blocking the sign-in configuration step. […]
Home/Active Directory Security/Active Directory Legacy Auth Deprecation 2026 Last Updated: July 2026 Answer capsule: Active Directory legacy auth deprecation in 2026 covers three separate but overlapping changes: CVE-2026-20833 forces domain controllers toward AES-SHA1 Kerberos tickets and away from RC4, NTLMv1 continues its multi-year phase-out through enhanced auditing, and Windows Server 2025 enables LDAP signing by
Fix “The Name Reference Is Invalid” in Active Directory After Exchange Decommission If you’ve recently decommissioned your last on‑premises Exchange server, you may run into the showInAddressBook name reference invalid error the moment you try to copy a user in Active Directory Users and Computers (ADUC). The error looks generic, but the cause is very
If you manage an internal Public Key Infrastructure, you already know that Active Directory Certificate Services fails quietly. A certificate authority can look “up” in Server Manager for months while its CRL silently expires, its audit filter sits at zero, or its request queue fills with thousands of failed enrollments nobody ever reviews. This AD
Flexible Single Master Operations (FSMO) roles are a critical component of Active Directory, ensuring consistency in a distributed multi-master environment. While most directory operations allow multiple domain controllers to accept updates, certain tasks like schema modifications, RID allocation, and time synchronization require a single authoritative source. In this deep technical guide, we explore all FSMO
The Real‑World Problem In real enterprise environments, DNS is never simple. You don’t just have one zone — you have: When a Domain Controller is decommissioned, DNS often keeps stale records behind: Manually checking and cleaning these across dozens (or hundreds) of zones is: The Solution – Core365 DNS Stale Record Scanner Core365-DNS-StaleRecord-Scanner is a
