What is AggregatorHost.exe and Why is it Running?

If you ever wondered what AggregatorHost.exe is and if it’s safe for your Windows PC, we’ve got the answer.

If you’re looking at Task Manager on a Windows computer, you might see AggregatorHost.exe running in the background. This could raise some questions. Is this a valid file? Is it a virus? Great questions. Let’s review what it is and if you should be concerned or not.

AggregatorHost.exe running in background as seen in Task Manager

What is AggregatorHost.exe?

To start, rest assured of this. AggregatorHost.exe is installed as a part of the Microsoft Windows operating system. It operates under the Windows Shell Experience Host process. This critical component helps enhance the overall user interface and graphical functionalities. You find AggregatorHost.exe in the “C:\Windows\System32” directory on your Windows PC.

locating AggregatorHost.exe in Explorer

As noted earlier, AggregatorHost.exe serves as a bridge between information sources and you, the user. It connects various system components and user interface elements. Its primary job is to present information from different sources in a unified interface. Here are some of its many functions:

  • Live Tiles and Notifications. This program is what manages the live tiles on the Start Menu. Those dynamic icons display real-time information from apps. This can include everything from weather updates to news headlines. It also includes calendar events and more.
  • Taskbar Previews. Have you ever wondered how the thumbnails pop up when you hover your mouse over an icon on the taskbar? AggregatorHost.exe is behind the scenes, generating and displaying these previews for you.
    Taskbar preview on Windows 11
  • Notifications and Action Center – AggregatorHost.exe is the maestro that orchestrates presenting notifications from various apps and system events. It also controls the Action Center, where you can review and respond to these notifications.

Is This File Safe?

The file is typically safe. AggregatorHost.exe is, after all, a legitimate Windows process. Still, it’s crucial to be aware of potential security and performance concerns:

  1. Malware Impersonation – Malicious software can disguise itself using filenames that resemble legitimate system processes, including AggregatorHost.exe. Always ensure that the process is located in the “C:\Windows\System32” directory and is digitally signed by Microsoft.
  2. Resource Usage – In some instances, you might notice AggregatorHost.exe consuming a significant amount of system resources like CPU or memory. This behavior could indicate an issue or conflict that requires investigation.

How to check if the file is signed digitally correctly?

As mentioned previously, first verify the file AggregatorHost.exe is located in the C:\Windows\System32 directory.
Depending on Windows versions you could right-click the file in explorer.exe and look at the Digital Signature tab. However, that isn’t always visible in later versions of Windows 11, so I’m going to show a method that works on all Windows versions by using PowerShell. No worries, it is a one-liner that you can copy and paste to run.

  1. Open PowerShell (no need to open it elevated)
  2. Type in the following command and parameters:

    Get-AuthenticodeSignature -FilePath C:\Windows\System32\AggregatorHost.exe | Format-List

  3. Read the result, in this case since it is a Microsoft Windows system file we want it to be signed by Microsoft, and verify the following lines:
    • Issuer: CN=Microsoft Windows Production PCA 2011, O=Microsoft Corporation, L=Redmond, S=Washington,
    • Status: ValidIf Issuer is the above, that indicates Microsoft issued the signing certificate. Next, the Status should read as valid. Those parameters together ensure that you can trust this file.

Don’t Worry, AggregatorHost.exe Is Usually Perfectly Legit

As we’ve discussed, AggregatorHost.exe is normally a valid Microsoft Windows system file. To be safe, you have to verify the file is recent, has the correct digital signature, and executes from the correct folder.




  1. dan

    November 28, 2023 at 9:51 am

    I don’t have the file AggregatorHost.exe on my Win 10 PC…how come?

    • Jeff Butts

      November 29, 2023 at 10:15 am

      Hi Dan,

      Not sure why it isn’t present, unless you’re just looking in the wrong directory. That said, if everything seems to be working properly in your operating system, I wouldn’t worry too much about it.

      Cheers, and thanks for reading!

      • dan

        November 29, 2023 at 4:03 pm

        I looked in “C:\Windows\System32” and used the EVERYTHING search utility; in both cases, nothing came up.
        I even ran an ‘sfc /scannow’ hoping it might be reinstated, but it didn’t do so.
        No matter, my overall user interface and graphical functionalities seem fine, so thanks for your reply.

  2. Sigge

    February 14, 2024 at 1:08 pm

    Thank you.
    I just saw this file running on my computer
    and I had never seen it before and I regularly
    check what’s running on my computer.
    I think that it (for me at least) came with
    the latest updates for windows 10
    that was completed this morning.

  3. Lothar

    February 16, 2024 at 5:22 pm

    I’m a hardcore nerd (Network packet sniffer, SQL db wrangler) since the early 1980’s, TRS-80 boxes with 300bps acoustic-coupler modems, and dial-up CompuServe, hehe.
    I completely nuked Aggregatorhost.exe from my Win10 box after reassigning ownership from TrustedInstaller to Users to change privs / perms on it, then deleting the exe.

    I’ve had *zero* issues with system notifications, taskbar previews, Live Tiles after killing the file and process.
    (The process had just installed itself randomly in 2024, when I’d previously disabled all User Telemetry Data collection via Task Scheduler, Services, and Opt-in/Out choices in Windows itself).

    Aggregatorhost owns phoning-home telemetry data on Win boxes, and that’s about it. Cheers.

  4. More Ron

    March 24, 2024 at 2:06 pm

    The above threads mentions the need for it to have “…the correct digital signature.” Mine does NOT have a digital signature from MS or anyone else. ZERO. So the answers to the plea for “what is it about?, needs to include “If it does NOT have a digital signature at all*, what should I do abut it?” *I used Task Manager route to “C:\Windows\System32” directory, and have not had problems except for strange activities I’ve not seen before, but sure would like to see what the experts are thinking on exactly [precisely] giving me advice on what to do to ensure it isn’t a Malware Trojan Horse (I’ve used various anti-malware and firewall apps with no findings at all).

    So please tell us if you have a step-by-step way to determine and then execute the non-digital signed program if it is not legit.

    I am using Win10 in a perfectly good Dell XPS only because Microsoft designed my hardware out.

    Sorry if this comes over as sarcastic comments = it is not intended, but expresses my so-far four-hour diving into the weeds search with nothing but bushes to whack again. Bless you all for trying to help.

    • Jeff Butts

      March 25, 2024 at 2:58 pm

      Hey Ron,

      It’s very unusual for that file not to have a digital signature at all. Let’s try to figure out what might be happening.

      Could you run this command in PowerShell and let us know the output?

      Get-AuthenticodeSignature -FilePath C:\Windows\System32\AggregatorHost.exe | Format-List


      Jeff Butts

      • More Ron

        March 30, 2024 at 12:38 pm

        Thanks, Jeff,

        I ran the PowerShell app and it confirmed it safe. I can’t find my (Win10) digital signature results since a couple days ago when MS installed an update. I’m not a guru anymore so I may have had a drop in my octogenarian brain capacity since a week ago, but I know for sure that when I did the taskmanager process back then, it showed a blank in the digital signature field.

        Here are the answers from PowerShell:

        SignerCertificate : [Subject]
        CN=Microsoft Windows, O=Microsoft Corporation, L=Redmond, S=Washington, C=US

        CN=Microsoft Windows Production PCA 2011, O=Microsoft Corporation, L=Redmond, S=Washington,

        [Serial Number]

        [Not Before]
        11/16/2023 11:20:08 AM

        [Not After]
        11/14/2024 11:20:08 AM


        TimeStamperCertificate : [Subject]
        CN=Microsoft Time-Stamp Service, OU=Thales TSS ESN:86DF-4BBC-9335, OU=Microsoft Ireland
        Operations Limited, O=Microsoft Corporation, L=Redmond, S=Washington, C=US

        CN=Microsoft Time-Stamp PCA 2010, O=Microsoft Corporation, L=Redmond, S=Washington, C=US

        [Serial Number]

        [Not Before]
        10/12/2023 12:07:09 PM

        [Not After]
        1/10/2025 11:07:09 AM


        Status : Valid
        StatusMessage : Signature verified.
        Path : C:\Windows\System32\AggregatorHost.exe
        SignatureType : Catalog
        IsOSBinary : True

Leave a Reply

Your email address will not be published. Required fields are marked *


To Top