Before you start
- Open Task Manager with Ctrl + Shift + Esc and look for unusually high CPU, Memory or Disk use.
- A restart is worth doing before deeper changes if the PC has been running for days.
Install Windows and optional driver updates
Go to Settings > Windows Update > Check for updates. Then open Advanced options > Optional updates and review driver updates.
Scan for malware
Go to Settings > Privacy & security > Windows Security > Virus & threat protection > Quick scan.
Free storage space
Go to Settings > System > Storage. Run Storage Sense or review Temporary files/Cleanup recommendations.
Disable unnecessary startup apps
Press Ctrl + Shift + Esc > Startup apps. Disable programs you do not need launching every sign-in. Avoid disabling security software or hardware-control utilities unless you know what they do.
Identify the heavy process
In Task Manager > Processes, sort by CPU, Memory or Disk. Close only applications you recognise. If one program is consistently high, update, repair or reinstall that program.
Optional: Best performance power mode
Go to Settings > System > Power & battery > Power mode > Best performance. On laptops this increases power use and heat, so use it when appropriate.
Microsoft source
This guide is independently written and condensed from current Microsoft Support guidance. If your Windows build differs or the problem persists, use the official source for the full decision tree.
Open Microsoft Support ↗