• Windows Defender Security Intelligence Updates (SIU)

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    I check wushowhide (WSH) daily to see what updates are pending. Nearly every day there is an SIU shown. Sometimes days go by with the SIU not being moved into the update queue. For example, WSH advised me on 9/14 that an SIU was available to hide. I NEVER hide these.  Daily, from 9/14 thru 9/19, WSH showed an SIU available. None has been listed in the update queue for downloading and installation so far. This is worrisome to me since I’m not receiving the latest coverage on a consistent basis.

    I also have had a driver listed daily in WSH for four days so far without appearing in the queue.

    On the other hand, I had an MSRT update listed in WSH during this period which moved onto the queue the next day.

    Any ideas on what might be happening here and how it might be corrected so I can update Defender in a timely manner?



    D. Eager

    Viewing 2 reply threads
    • #2390654

      Hi Don!

      Windows Defender is going out on its own and getting these SIUs completely separately from WU. It doesn’t need WU to get these, as a matter of fact.

      On my systems, I can disable WU’s services and still manually update the definitions/signatures/SIUs from within Windows Defender (or Microsoft Defender, for those who wish to call it that).

      I have even made sure this behavior is the default by using settings within Group Policy on Windows 10 Pro. I wouldn’t be too surprised to learn from others here that there might be an equivalent setting to use within the registry for those on Windows 10 Home.

      BTW, I’m on 21H1 Pro x64.

      I hope this helps!

      1 user thanked author for this post.
    • #2390658

      I just determined that these daily updates DO appear in the WinUpdatesList app, where I didn’t look previously. So it appears that they are actually posting. I can drop this from my list of things to worry about! I’m wondering why the SIU updates that are posting without actions don’t show in Windows Update>View Update History>Definition Updates as do the ones that pass through WSH?


      Don E.

      • #2390660

        I’m wondering why the SIU updates that are posting without actions don’t show in Windows Update>View Update History>Definition Updates as do the ones that pass through WSH?

        Probably because WU didn’t touch them, they were handled by Windows Defender directly. Same thing goes for me…the SIU updates that WU doesn’t install aren’t listed in the WU Update History at all, yet I still have them.

        Occasionally, upon first booting one of my computers up, I’ll get a notification from WU that there are updates to install. Upon clicking on the notification, I then usually find that the needed update(s) are for Windows Defender. I then go look in Windows Defender to see that Defender has already installed them, at which time I click on the “download and install” button in WU. After about a second or two, WU suddenly shows that I’m already up to date.

        Like you said, this behavior makes for one less thing to worry about or get grey hairs over.  😉

    • #2408454

      I’m comparing Avast Free to Defender. One article said defender had to be updated manually through windows update..a total deal killer for me since I pause windows update to avoid being a beta tester. It sounds like defender updates in the background just like Avast without windows update involvement.

      • #2408480

        Defender does indeed update itself in the background without the help of Windows Update…it has its own built-in update mechanism just for that. This mechanism updates the signatures (which are released randomly about four times a day) on a daily basis as well as the engine and the anti-malware client itself about once a month or so. From my experience, the signatures are only updated by Defender’s mechanism once a day, so if you want the signature updates more frequently, you’ll have to go into Windows Security and select “Virus & threat protection” and then scroll down to where it says “Virus & threat protection updates”. Just below that listing is a clickable blue-colored link that says “Check for updates”. Clicking it will bring you to the manual update page. Simply click the grey button labeled “Check for updates”, and Defender will take it from there.

        As far as Avast Free, be wary of pop ups for other products they offer. These can be controlled (based upon statements made by folks in their support forums), but I haven’t found any firm reference yet to being able to completely disable them. I also found a few folks claiming that the pop ups can’t be disabled at all in the Free edition of Avast. Just Google the term “Avast Free pop ups” and check out the hits that come from the Avast forums. Some of them date back to 2015, but there are more recent hits from 2020 and 2021 as well. I found a thread that shows how to put Avast info something like a silent mode, but then folks complain about a periodic pop up telling them that the program is in silent mode. Six of one half dozen of the other, I guess.  😐

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