I have my Windows Updates set to notify me and then I check them and install them daily so they aren't downloded automatically. Since October 11th Windows Defender hasn't been appearing in Windows Updates. I've tried some troubleshooting so I'll give some history and explain what I've done so far without success.
October 11, 2021 was the last update of definitions I got through Windows Updates properly.
I didn't receive any on the 12th but it happens at times that there are none for a day so didn't think anything of it.
The next updates (not for Windows Defender) that did come through were:
October 13 - October 2021 Security and Quality Rollup for .Net Framework KB006763
October 13 - Windows Malicious Software Removal Tool x 64 (KB890830 as always)
October 13 - October 2021 Security Monthly Quality Rollup for Windows 8.1 x64 (KB5006714)
Still nothing for Windows Defender. I began to wonder why and was going to look into it but hadn't yet and then I got a pop up message saying my WD was out of date on the 18th. So I updated it manually from the user interface and thought that might trigger it to start working again and it seems it did because I received updates the proper way on :
October 19 - Windows Defender update came through updates as usual
October 20 - Again the update came through as usual
So I thought it was fixed but on the 21st I didn't get any again. I checked online to see what the latest version was and it was later than what I had so it had stopped working again.
At this point I ran the Windows Update troubleshooter. It said it fixed few things in the configuration so I thought that would take care of it but it did not.
So I started looking at other things to try. I went to the Microsoft download site and downloaded the definitions update file for the 64-bit version of Windows 8.1 and I thought it wouldn't work because it didn't seem to do anything when I clicked on it as I only had the circle for a couple of seconds but it turns out it did because WD was updated to the latest version after doing that. I thought that might fix the problem but it didn't either.
So I decided to check the Event Viewer for errors and there was one for Windows Updates which seems to indicate a problem with the Windows Update Agent. The Event ID: 25 error says "Windows Update failed to check for updates with error 0x8024000E". I checked to make sure I had the proper version of the Windows Update Agent (KB2919355) installed by verifying the version of the wuadeng.dll file and it was version 7.9.9600.19915 that was last updated on December 14, 2020 which seems to be the correct one.
I checked for updates manually from the Control Panel and then I got the following Information events in the Event Viewer for Windows Updates:
Event ID: 26 "Windows Update successfully found 0 updates
Event ID: 26 "Windows Update successfully found 7 updates
Event ID: 40 "An update was detected" (7 entries so I assume one for each of the 7 found updates).
The above all occur every time I run Windows Updates manually.
So that's where I'm at now. I know there are other measures to be done like stopping services and whatnot but thought I'd ask for some direction on the next steps to try. For sure malware is not an issue. I ran MalwareBytes and also used FRST to make sure there was nothing suspicious.
Tech Support Guy System Info Utility version 1.0.0.9
OS Version: Microsoft Windows 8.1 Pro, 64 bit, Build 9600, Installed 20140310170059.000000-240
Processor: Intel(R) Core(TM) i5-4670 CPU @ 3.40GHz, Intel64 Family 6 Model 60 Stepping 3, CPU Count: 4
Total Physical RAM: 8 GB
Graphics Card: Intel(R) HD Graphics 4600, 1024 MB
Hard Drives: C: 917 GB (795 GB Free);
Motherboard: LENOVO SHARKBAY, ver 0B98401 PRO
System: LENOVO, ver LENOVO - 1480, s/n MJ00CJ6B
Antivirus: Windows Defender, Enabled and Updated
October 11, 2021 was the last update of definitions I got through Windows Updates properly.
I didn't receive any on the 12th but it happens at times that there are none for a day so didn't think anything of it.
The next updates (not for Windows Defender) that did come through were:
October 13 - October 2021 Security and Quality Rollup for .Net Framework KB006763
October 13 - Windows Malicious Software Removal Tool x 64 (KB890830 as always)
October 13 - October 2021 Security Monthly Quality Rollup for Windows 8.1 x64 (KB5006714)
Still nothing for Windows Defender. I began to wonder why and was going to look into it but hadn't yet and then I got a pop up message saying my WD was out of date on the 18th. So I updated it manually from the user interface and thought that might trigger it to start working again and it seems it did because I received updates the proper way on :
October 19 - Windows Defender update came through updates as usual
October 20 - Again the update came through as usual
So I thought it was fixed but on the 21st I didn't get any again. I checked online to see what the latest version was and it was later than what I had so it had stopped working again.
At this point I ran the Windows Update troubleshooter. It said it fixed few things in the configuration so I thought that would take care of it but it did not.
So I started looking at other things to try. I went to the Microsoft download site and downloaded the definitions update file for the 64-bit version of Windows 8.1 and I thought it wouldn't work because it didn't seem to do anything when I clicked on it as I only had the circle for a couple of seconds but it turns out it did because WD was updated to the latest version after doing that. I thought that might fix the problem but it didn't either.
So I decided to check the Event Viewer for errors and there was one for Windows Updates which seems to indicate a problem with the Windows Update Agent. The Event ID: 25 error says "Windows Update failed to check for updates with error 0x8024000E". I checked to make sure I had the proper version of the Windows Update Agent (KB2919355) installed by verifying the version of the wuadeng.dll file and it was version 7.9.9600.19915 that was last updated on December 14, 2020 which seems to be the correct one.
I checked for updates manually from the Control Panel and then I got the following Information events in the Event Viewer for Windows Updates:
Event ID: 26 "Windows Update successfully found 0 updates
Event ID: 26 "Windows Update successfully found 7 updates
Event ID: 40 "An update was detected" (7 entries so I assume one for each of the 7 found updates).
The above all occur every time I run Windows Updates manually.
So that's where I'm at now. I know there are other measures to be done like stopping services and whatnot but thought I'd ask for some direction on the next steps to try. For sure malware is not an issue. I ran MalwareBytes and also used FRST to make sure there was nothing suspicious.
Tech Support Guy System Info Utility version 1.0.0.9
OS Version: Microsoft Windows 8.1 Pro, 64 bit, Build 9600, Installed 20140310170059.000000-240
Processor: Intel(R) Core(TM) i5-4670 CPU @ 3.40GHz, Intel64 Family 6 Model 60 Stepping 3, CPU Count: 4
Total Physical RAM: 8 GB
Graphics Card: Intel(R) HD Graphics 4600, 1024 MB
Hard Drives: C: 917 GB (795 GB Free);
Motherboard: LENOVO SHARKBAY, ver 0B98401 PRO
System: LENOVO, ver LENOVO - 1480, s/n MJ00CJ6B
Antivirus: Windows Defender, Enabled and Updated