How to Fix Windows Modules Installer Worker High CPU

What Causes This?

Windows Modules Installer Worker, also called TiWorker.exe, is part of Windows Update. It usually spikes CPU usage when Windows is checking for updates, installing them, or cleaning up old update files in the background. High CPU can last longer if update files are stuck, the Windows Update cache is corrupted, or your PC has a lot of leftover update components to process.

Common Symptoms

• CPU usage stays unusually high in Task Manager because of Windows Modules Installer Worker
• Fans run louder than normal and the PC feels hot or sluggish
• Apps open slowly or stutter while Windows is idle
• High disk usage happens at the same time as the CPU spike
• The problem comes back after every reboot or update check

How to Fix It Manually

1. Check if Windows Update is actively running

   1. Press Ctrl+Shift+Esc to open Task Manager.
   2. On the Processes tab, look for Windows Modules Installer Worker or TiWorker.exe.
   3. If CPU usage is high, wait 10-20 minutes to see if it drops on its own. Short spikes are normal during updates.

2. Install any pending Windows updates

   1. Press Windows + I to open Settings.
   2. Go to Windows Update.
   3. Click Check for updates.
   4. Install everything available, including optional quality updates if relevant.
   5. Restart your PC after the updates finish.

3. Run the Windows Update troubleshooter

   1. Open Settings with Windows + I.
   2. Go to System > Troubleshoot > Other troubleshooters.
   3. Find Windows Update and click Run.
   4. Apply any fixes it suggests, then restart the PC.

4. Clear the Windows Update cache

   1. Press Windows + S, type cmd.
   2. Right-click Command Prompt and choose Run as administrator.
   3. Run these commands one at a time:

      net stop wuauserv
      net stop bits
      net stop cryptsvc
      ren C:\Windows\SoftwareDistribution SoftwareDistribution.old
      ren C:\Windows\System32\catroot2 catroot2.old
      net start wuauserv
      net start bits
      net start cryptsvc

   4. Restart your PC and check CPU usage again.

5. Repair corrupted system files

   1. Open Command Prompt as administrator.
   2. Run:

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

   3. Let both scans finish completely. This can take a while.
   4. Restart your PC when done.

6. Clean up old update files

   1. Press Windows + S, type Disk Cleanup, and open it.
   2. Select your C: drive.
   3. Click Clean up system files.
   4. Check items like Windows Update Cleanup, Temporary files, and Delivery Optimization Files.
   5. Click OK to remove them.

7. Check Task Scheduler maintenance

   1. Press Windows + S, type Task Scheduler, and open it.
   2. Browse to Task Scheduler Library > Microsoft > Windows > Servicing.
   3. If servicing tasks are repeatedly failing or retriggering, complete the update and repair steps above first. Repeated failures usually point to update corruption rather than a process you should disable.

Fix It Automatically with Kudu

Kudu can scan for Windows Update leftovers, temporary files, and other system clutter that keeps Windows Modules Installer Worker busy longer than it should. It helps clean up the junk safely and optimize background activity so your PC runs smoother without digging through update folders and system tools yourself.

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