Laptop slow starting up – Svchost using 98% of processor (CPU) cycles

Problem

Why is my Dell Inspiron laptop slow starting up – takes several minutes to boot fully into Windows 7 every time it starts up? It runs normally after it is fully booted, but repeats the slow startup every time it is switched on.

I pressed the Ctrl + Alt + Del key combination in order to find out what the processor usage is under the Performance tab of the Windows Task Manager, which showed the CPU as working at 100% under the Processes tab. A service called SVCHOST.EXE was shown as using 98% of processor time. There were several other entries for SVCHOST.EXE, with each of them showing as using zero processor time and different amounts of memory. Is my computer infected by a virus?

Answer

No, your computer is probably not infected by malware. Here is what Microsoft says about Svchost: “Svchost.exe is a process on your computer that hosts, or contains, other individual services that Windows uses to perform various functions. For example, Windows Defender uses a service that is hosted by a svchost.exe process.

“There can be multiple instances of svchost.exe running on your computer, with each instance containing different services. One instance of svchost.exe might host a single service for a program, and another instance might host several services related to Windows. You can use Task Manager to view which services are running under each instance of svchost.exe.”

This problem is still happening in Windows 10. To access Windows Update in Win10, use the Search box to provide a link to it because it is no longer in the Control Panel. Here is a forum post on the problem:

svchost.exe High CPU Usage [Windows 10] –

http://www.tomshardware.co.uk/forum/id-2855055/svchost-exe-high-cpu-usage.html

What is svchost.exe? –

http://windows.microsoft.com/en-gb/windows/what-is-svchost-exe#1TC=windows-7

To open the Windows Task Manager in Win7, press the Ctrl-Alt-Del key combination, click on Start Task Manager. In Task Manager, click on the CPU tab, which shows the processor usage as a percentage use by each process.

Svchost (short for Service Host) is a small .exe system file that is part of Windows, which uses it to load services or groups of services. Each group of services loads as a separate process. That is why there are multiple instances of Svchost.exe shown under Processes. It (or they) can hog the processor’s time to such an extent that the mouse becomes difficult to control because it lags behind when you try to move it across the screen.

There is an excellent Microsoft utility called Process Explorer from Windows Sysinternals that can tell you which service/services are responsible for the high processor usage.

Process Explorer v16.12 –

https://technet.microsoft.com/en-gb/sysinternals/bb896653.aspx

“Installation: Simply run Process Explorer (procexp.exe). The help file describes Process Explorer operation and usage. If you have problems or questions please visit the Sysinternals Process Explorer Forum.”

Run the program when processor usage is high and then wait until the Process Explorer window appears. You look down the processor column to find out which process is using most of the processor time. It lists all of the running processes and provides a description of each of them and the processor time that it uses. When minimised, it shows as an icon in the System Tray (Notification Area). When the mouse pointer is held over the icon, it shows the current processor usage and the name of the process with the highest processor use.

Process Explorer shows which services each instance of Service Host (svchost) is running. You will probably discover that the problem is caused by Wuauclt.exe, which is the Windows Update service.

You can try using the following fix. Enter services.msc in the Start => Search box to bring up the Services window.

Note well that you should always make a system backup or at least create a restore point in System Restore before making any changes to the system so that you can get it back to where it was before the change(s) were implemented.

Locate the Automatic Updates service. Visit this link http://go.microsoft.com/fwlink/?LinkId=43264. It will offer to download a file called WindowsUpdateAgent20-x86.exe. Don’t run it until you’ve done the following. Use Windows Explorer (right-click Start => Explore) to located C:\WINDOWS\SoftwareDistribution. (File Explorer in Win10.) You can use the Search box to provide a link to it.) Right-click on the SoftwareDistribution folder and use the Rename facility to rename it as SoftwareDistributionX. Locate the C:\Windows\ WindowsUpdate.log (use the Start => Search facility if necessary) and rename it WindowsUpdateX.log. Now run the downloaded WindowsUpdateAgent20-x86.exe file and restart the computer.

If doing that doesn’t work Open Windows Explorer (File Explorer in Win10) and try deleting the contents of the C:\WINDOWS\System32\Catroot2 folder. The folder itself must not be deleted, just its contents.

If none of these fixes works, you should just disable Windows Update (in the Start => Control Panel), and remember to check the Windows Updates site – http://update.microsoft.com/ – for updates every week. If your PC is fully updated, the Windows Update service won’t run to cause the problem.