This only started two days ago. I rebooted to see if that would help, but to no avail. Not sure if it is a windows update problem or an MSE problem. NB: A few days ago i got that malware warning message during the scan, but there was nothing found - I read the post here. Not sure if it triggered this strange behavior.
Have you tried updating MSE directly from the MSE Update tab shown on the MSE program window.
Yes and it went through the usual steps: Searching for updates, downloading and installing. Got the green progress bar as well. It then indicated that it updated. Got the green tick too. You'll notice in the lower window it shows the latest def file as installed. It is only windows update that showed the updates as an unsuccessful install.
Now that you have pointed that out I had the same problem yesterday with MSE 1.239.713.0 that Windows Update showed as failed 3 times, but the MSE program itself was updated with that update number, but Windows Update was still showing it as Failed.
All seems to be working again today & 1.239.797.0 is showing as successfully updated in Windows Updates, so I don't know what's going on. I will see what happens tomorrow.
Many people running Windows 10 have been complaining about Windows Defender not updating when using Windows Update. (Windows Defender is just a renaming of Microsoft Security Essentials. They both use the same definitions.) The WD issue has been going on for at least 5 days on my machines.
Windows Update Error 0x80070643 for Windows Defender - - Windows 10 Forums
I suspect that MSE is also experiencing update issues. We've received information on Ten Forums that Microsoft is aware of the problem and working to find a fix. Hopefully it will be included by next week (4/11/17) on Patch Tuesday, if not sooner. In the meantime updates for MSE should work by doing it manually from the MSE dashboard or by going to the Microsoft Malware Protection Center.
On Windows Defender Definition Update error 0x80070643 - - Windows 10 Forums
Tnx everyone who responded.
This morning when I logged on, a new def file was sent and MSE updated (i.e. via WU). WU and MSE show that the install was successful. I see that MS sent out a fix this morning.
What's New - Microsoft Malware Protection Technologies
Thanks also for that info. Clicking on Painter's link the latest MSE update should have the fix required & that Update Fix Definition is 1.239.874.0.
I checked on my MSE updates & that one was installed this morning, but I had to install it via the MSE Dashboard. So hopefully it will now update properly.
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