15 Windows 10/11 Built-in Useful Tools You Should Know (Free, No Install)

Hello my friend! Many people download program from internet to fix or check computer, but actually Windows already have many useful tool for free. No need install anything, no virus risk! Today I share with you 15 Windows built-in tool you should know, with Run command so you can open it fast. Let's start!

💡 How to use Run command: Press Windows + R, type the command, and press Enter. For command with (Admin), search Command Prompt in Start, right click and choose Run as administrator.

📊 Tool 1: Task Manager

See what program is running, close program that freeze, and check CPU, RAM, disk and network.

Open: Ctrl + Shift + Esc
Useful for:
- Processes tab — find which program use most CPU or RAM, click End task to close it.
- Startup apps tab — disable app that start with Windows, make computer boot faster.
- Performance tab — see your CPU, RAM, GPU model and how much you use.

🔍 Tool 2: Resource Monitor

Task Manager but more detail. You can see which program use your internet, or which file is lock by program.

Open: resmon
Useful for:
- Network tab — see which program is upload or download.
- CPU tab > Associated Handles — search file name to find which program is using it (when Windows say "file is open in another program").

📈 Tool 3: Reliability Monitor

Very underrated tool! It show history of crash, error and update day by day in a nice chart. Easy to find "computer start have problem after I install what?".

Open: perfmon /rel
Useful for: Red X mean program crash or Windows error. Click on the day to see detail.

📜 Tool 4: Event Viewer

Windows write log of everything. When computer restart by itself or blue screen, you can check here.

Open: eventvwr.msc
Useful for: Go to Windows Logs > System and look for Error or Critical.

💡 Tip: Event Viewer have many warning, this is normal. Don't scare! Only look at error near the time you have problem.

🛠️ Tool 5: System File Checker (SFC) and DISM

Windows file broken make computer have strange error. This 2 command can repair it.

Open: Command Prompt (Admin), then run:

DISM /Online /Cleanup-Image /RestoreHealth
sfc /scannow

Run DISM first (it fix Windows image), then SFC (it fix system file). Wait until 100% and restart computer.

🧠 Tool 6: Windows Memory Diagnostic

Computer blue screen often or freeze randomly? Maybe RAM have problem. Test it!

Open: mdsched
Choose Restart now and check for problems. Computer will restart and test RAM. Result show after login.

💽 Tool 7: Check Disk (CHKDSK)

Check hard disk or USB for error and bad sector.

Open: Command Prompt (Admin), then run:

chkdsk C: /f

For Drive C, Windows ask to check on next restart. Type Y and restart.

💡 Tip: You can also right click drive in File Explorer > Properties > Tools > Check.

🗄️ Tool 8: Disk Management

Create, delete, resize partition, or give drive letter to new hard disk or USB that not show in File Explorer.

Open: diskmgmt.msc (or right click Start button > Disk Management)

⚠️ Warning: Be very careful! Delete wrong partition = lost all data. Always backup first.

🖥️ Tool 9: Device Manager

See all hardware in your computer, update or reinstall driver.

Open: devmgmt.msc
Useful for: Yellow mark ⚠️ mean driver have problem. Right click > Update driver or Uninstall device then restart (Windows will install again).

ℹ️ Tool 10: System Information

Full detail about your computer: model, BIOS, CPU, RAM, motherboard, and more.

Open: msinfo32
Useful for: Ask help from IT, check spec before buy second hand computer, or find your laptop model to download driver.

🧹 Tool 11: Disk Cleanup

Delete temp file, old Windows update, and other junk to free Drive C.

Open: cleanmgr
Click Clean up system files to delete more.

📦 Tool 12: Windows Sandbox

A safe "fake computer" inside your computer. Test program you don't trust, when you close Sandbox, everything is delete. Your real computer is safe.

Need: Windows 10/11 Pro, Enterprise or Education (not Home), and virtualization turn on in BIOS.
Turn on: Press Windows + R, type optionalfeatures, tick Windows Sandbox, click OK and restart.
Open: Search Windows Sandbox in Start.

🔣 Tool 13: Character Map

Open: charmap

💡 Tip: For emoji and common symbol, Windows + . is more fast.

🛡️ Tool 14: Windows Security

Free antivirus, firewall and ransomware protection already in Windows.

Open: Search Windows Security in Start.
Useful for: Virus & threat protection > Scan options > Full scan or Microsoft Defender Offline scan for hard virus.
Turn on Ransomware protection > Controlled folder access to protect your Documents and Pictures folder.

🤝 Tool 15: Quick Assist

Help friend or family fix computer from far away. Free from Microsoft.

Open: Search Quick Assist in Start.
Helper click Help someone and get a code, the other person type the code and click Allow.

⚠️ Warning: Never give Quick Assist code to stranger who call you. Microsoft will never call you to fix your computer!

📋 Run Command Cheat Sheet

Save this table for quick use!

Tool	Run command
Task Manager	`taskmgr`
Resource Monitor	`resmon`
Reliability Monitor	`perfmon /rel`
Event Viewer	`eventvwr.msc`
Memory Diagnostic	`mdsched`
Disk Management	`diskmgmt.msc`
Device Manager	`devmgmt.msc`
System Information	`msinfo32`
Disk Cleanup	`cleanmgr`
Windows Features	`optionalfeatures`
Character Map	`charmap`
Control Panel	`control`
System Properties	`sysdm.cpl`
Programs and Features	`appwiz.cpl`
Network Connections	`ncpa.cpl`
Power Options	`powercfg.cpl`
Services	`services.msc`
DirectX Diagnostic	`dxdiag`
Windows Version	`winver`

Conclusion

Before you download any "PC cleaner" or "PC booster" program from internet, try this built-in tool first. It free, safe, and made by Microsoft. Many of my computer problem I fix only with Task Manager, Reliability Monitor and sfc /scannow. Hope this help you! If you have favorite tool, share with me in comment. Thank you!

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