What is SearchFilterHost.exe and Why is it Running?

Have you ever wondered what SearchFilterHost.exe is doing on your computer? Here’s an overview of some of the technical information regarding it.

So you opened up task manager and saw SearchFilterHost.exe running, and you want to know what it is, right? You’re probably in the clear as this process isn’t normally a virus. In fact, it’s included with every copy of Windows since XP, but it wasn’t heard of much until Vista. This little executable is a system service created by Microsoft that aids Windows Search functions.

Want to know more? Let’s dive in.

task manager searchfilterhost.exe view

If you look in Process Explorer, it doesn’t reveal much about SearchFilterHost, but it does let us know that it is a child of SearchIndexer.exe, which we covered in a previous article. If you want to disable the service for some reason, it can be done following those instructions. SearchFilterHost.exe normally doesn’t use much memory or CPU power and is generally light on system resources; however, there have been a few rarer complaints we’ll talk about below.

process explorer

A look at netmon reveals that this process has some network activity where it contacts Microsoft and downloads data. The data transmitted is not personal; it is related to queries for help topics within Windows built-in help system and goes directly to Microsoft. This network activity can be disabled by opening the Help Topics box in Windows and then into Options > Settings and unchecking the “Improve my search results by using online Help.”

help settings improved search results


Registry keys affecting SearchFilterHost are located at:

  • HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Diagnostics\Performance\Resolvers
    • Reg_Expand_SZ: SystemBinariesList
  • Also, a few entries regarding network access through the firewall at:
    • HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\services\SharedAccess\Parameters\FirewallPolicy\RestrictedServices\Static\System

The process itself is located at

  • C:\Windows\System32



Some users have reported that SearchFilterHost uses a high CPU usage, up to 100%,  from time to time. If you are encountering this issue, there isn’t necessarily a hard fix. One user suggests setting up an image redirect for the service’s launch that will autokill it. Another suggested disabling XML indexing. Some suggest disabling Windows search, and others have had to reformat the operating system to fix it.

In many of the cases reported, the high CPU use was related to installing a third-party decoder.


SearchFilterHost.exe is a safe process created by Microsoft. It is essential for some functions of Windows Search to work properly. However, a search is still capable of working (less fully) without it. The process doesn’t normally have a noticeable impact on system performance and shouldn’t be disabled on a whim.



  1. Brent

    June 6, 2014 at 10:31 pm

    My SearchFilterHost continually takes up 100% of CPU, is reported by Norton about every 10 minutes for high CPU usage, and I have never installed anything but bare bones windows 8 and MS office. It sucks and is a waste.

  2. Marc G

    March 24, 2015 at 9:14 am

    What is an example of “third-party decoder”

    • udaya

      August 22, 2018 at 11:26 pm

      i have this question

  3. Ali

    April 14, 2015 at 8:04 am

    Thank you for the Nicely detailed post. Really appreciate your work.

  4. Jay Paxton

    October 28, 2015 at 12:41 pm

    What is SearchFilterHost.exe and Why is it Running?

    You never said anything about an easy way to get ride of this CPU Pig.
    It would be helpful to others if you could add a sure way of deleting these files from the System32 folder on XP Windows.

    Not everybody is going to Windows 7, 8 or 10 because you have no control over your computer with those nasty OS’s.

    I feel sorry for people who are having to switch from the faithful and reliable XP OS’s.

    I value my privacy and freedom to much to allow myself to be market materiel for big corporations to data farm your every move and every existing moment, even while you sleep.

    They are trying their best to infiltrate Win XP with their data farming files like this SearchFilterHost.exe does.

    I never had any issues with my computer until just lately it took over my Windows Explorer search option and if I wanted to use it I had to use the “click here to use the search companion”.

    I own my computer and I want to have the right to go into any folder I chose and delete files and folder at my own risk and not be denied by any OS like Win, 7, 8, 8.1, and 10.

    Those OS’s interface, Desktops look like Win 95.
    They took parts of Win 95, 98SE, Xp and added made them so you couldn’t edit your system to to stop the invasion and data farming your personal life.

    • KirkH420

      July 27, 2021 at 2:17 pm

      “search companion” is almost 100% of the time related to: YOU have installed some sort of toolbar.
      More often than not, this happens when you downloaded and installed some Freeware/Shareware. You are responsible for what is on your machine regardless of how it got there, especially illegal things. When you install anything, you need to read every page of the installer and you MUST watch for checkboxes and radiobuttons. Freeware usually comes with some “Bonus Extras” which you do not want on your machine and they ALWAYS are preset as YES-install. These toolbar things (google toolbar, ask toolbar, bing toolbar), while they might have the name of a reputable company they are using those toolbars to track every single thing you search for and probably a lot more than that.

      The only way to avoid this type of thing is to be vigilant against installing Freeware. You should ALWAYS choose an Open Source option for all your software needs unless you prefer to pay for brand name software. You should keep in mind that just because you Paid for some software, that does not mean that they aren’t selling your data. So again I will give credit to the Open Source community, you will not find such things there. Open Source means that any Coder could open the software’s source code, look at it’s guts, see how it works and if were any malicious code it would become public information pretty quick.

  5. Jay Paxton

    October 28, 2015 at 12:46 pm

    Oh..I forgot to tell you how to get rid of that trash..
    use File ASSaSSIN to delete those files.
    there’s about 4 or 5 of them, all right together.
    if you get a cant delete message don’t worry, just keep ahmmering them and soon FileASSASSIN will delete them.

    • Jack Sparrow

      January 16, 2018 at 5:57 am

      Jay Paxton – you’re a tool. Take your tinfoil hat and gtfo.

      • KirkH420

        July 27, 2021 at 2:29 pm

        There’s nothing pathetic than the types of “computer users” who refuse every new version of Windows. That guy really thinks staying on the MOST hackable and MOST targeted for hacking version of windows still in existence?
        There are Penetration Testing classes teaching that exact thing as intro to hacking 101 (you want to learn about hacking, go to, they have tutorials and some of the first machines you need to learn to compromise are XP hosts). That guy might be one of the worse ones because usually they whine about upgrading until the security support ends and in this case he should have moved to 7 when that happened. When he does end up using a newer OS he’s not going to understand anything about it which will make him 10x more vulnerable than my Grampa using his win10 PC.

  6. Yatsura

    June 4, 2019 at 3:38 pm

    There is no tinfoil needed anymore, since the news started talking about NSA contracts with Microsoft to observe everyones homes via X-Box-Kinect-Cameras.

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