Active Directory is still the centre of most Windows estates. These guides cover running domain controllers safely, locking down admin access, keeping the directory clean, and working out why a Group Policy did or did not apply.
Start here
- Active Directory Tiered Administration Model: A Practical Setup Guide
- Find and Remove Stale Computer Accounts in Active Directory
- Group Policy Troubleshooting: GPResult and Event Logs
- PowerShell Active Directory Management: Complete Guide
Domain controllers and design
- Active Directory Tiered Administration Model: A Practical Setup Guide
- Add Secondary Domain Controller to Domain
- How to Set Up a Read-Only Domain Controller (RODC)
- How to Transfer FSMO Roles to a New Server
- Transfer Infrastructure Master FSMO Role Guide
- How to Decommission a Domain Controller (Server 2022/2025)
- DNS Scavenging in Active Directory: Setup and Pitfalls
- Recover a Windows Domain Controller on AWS: Full Guide
Keep the directory clean
- Find and Remove Stale Computer Accounts in Active Directory
- Inactive Computers Active Directory
- Restore Deleted AD Objects: AD Recycle Bin and PowerShell
- Active Directory Password Expiration Alert
Reporting with PowerShell
- PowerShell Active Directory Management: Complete Guide
- Import Active Directory PowerShell Module 2026
- Export Active Directory OU Members to CSV Using PowerShell
- Export Active Directory Users Guide
- PowerShell Export AD Groups Script
- Get All Users in AD Group PowerShell
- Active Directory PowerShell Script
- How to Get an OU Distinguished Name in PowerShell
Group Policy
- Group Policy Troubleshooting: GPResult and Event Logs
- Group Policy Corruption Fix Guide
- Group Policy Error 0x8007000d: Server Fix Guide
- How to Reset Group Policy Settings to Default
- Windows Group Policy ADMX Guide
- Group Policy Templates Catalog
- Windows Update Group Policy: Complete Configuration Guide
- Windows Remote Desktop Group Policy
- Windows Firewall Group Policy Guide
- Disable OneDrive Group Policy Guide
Tools that help
- AD Health and Security Audit: a client-ready AD health and security report
- GPO Health and Cleanup Report: find empty, unlinked and conflicting policies
- AD CS Certificate Health Report: CRL, expiry and ESC1 risk across your PKI