The good stuff, cut through the noise.

Real-time file system, registry, and process/thread activity monitoring. Indispensable for diagnosing application misbehavior on Windows.

Task Manager on steroids. Shows full process trees, DLL handles, parent/child relationships, and per-process CPU/memory in real time.

Browser and editor for Active Directory. View object attributes, compare snapshots, and navigate the directory tree without ADUC limitations.

Shows the resultant set of Group Policy for a user or computer. Run gpresult /H report.html for a full HTML breakdown of applied policies.

The main hub for user management, licensing, and service health. Bookmark the service health page — it's the fastest way to rule out Microsoft outages before digging in.

The modern replacement for all the individual O365 PowerShell modules. One SDK to rule M365. Takes time to learn the permission scopes but worth it for automation.

Test mail flow, Autodiscover, ActiveSync, and more from Microsoft's own infrastructure. Useful for DNS and mail routing troubleshooting without needing external tools.

DNS lookups, MX record checks, SPF/DKIM/DMARC validation, blacklist checks. The go-to for mail flow and DNS debugging. The SuperTool is especially handy.

Built into IIS. Captures detailed per-request execution traces for slow or failing requests. Essential for diagnosing app pool CPU issues and latency by endpoint.

Captures memory dumps of w3wp.exe on CPU threshold triggers. Use with WinDbg or Visual Studio to analyze hang and high-CPU conditions in IIS worker processes.

Extends IIS logging with custom fields, real-time log viewing, and response time tracking. Useful when the default W3C log fields aren't enough for diagnosis.

The standard SQL Server GUI. Use the Activity Monitor and DMV queries for live performance analysis. Keep it updated — each release adds useful diagnostics.

Adam Machanic's stored procedure for real-time SQL Server session monitoring. Far more useful than sp_who2 for identifying blocking, waits, and expensive queries in production.

Acumatica's built-in OData feed for reporting and integration. See the KB article on filter syntax before you spend an hour debugging why your query returns nothing.

The best PowerShell authoring environment. IntelliSense, integrated terminal, Git, and the PowerShell extension make script development far less painful than the ISE.

Run PowerShell 7 alongside Windows PowerShell 5.1 — don't replace it. PS7 has better error handling, parallel ForEach-Object, and cross-platform compatibility.

Windows Task Scheduler is underrated for IT automation. Use schtasks /query /fo LIST /v to audit all tasks on a machine — useful when something is running at unexpected times.

Network discovery and security scanning. Use it to audit what's actually exposed on your network — often surfaces forgotten services and open ports that shouldn't be there.

Validates your email authentication records. Run this any time you change MX or SPF records to catch misconfigurations before they cause mail delivery issues.