Windows 10 AE, Microsoft Security Client Error code: 0x80070426

Hi,

We are glad to know that you have upgraded your computer to Windows 10.

To help you with your concern, kindly refer to the article provided by Syed N on this link.

Thank you.

My computer was already running W10, this problem occurs since I upgraded to Anniversary Edition.

The article in the link refers to Vista, not W10.

It also refers to the error occurring with Windows Update, whereas mine is a dialog box that pops up after a reboot and logon.

I tried following the instructions anyway but do not have a service called Software Licencing - presumably this exists in Vista but not W10?

Have run sfc/scannow, problem persists.

Thanks to anyone that can help.

No fix found. Whenever I power-cycle, then after the first logon I get that same error.

Fortunately I rarely power-cycle and it seems not to happen after sleep.

Whenever I see the error I click OK to close the error dialog and then manually start the Defender desktop app just to check it is working.

Interestingly, I did this just now and the first time it showed the same error dialog.

I closed the new error dialog and tried again and Defender started OK  (the UI came up and now after closing that window the Defender Icon is in the System Tray)

So it seems to be timing related. Once the PC has started up and settled down all is OK, but if Defender tries to start too soon it fails. Well, it looks like that from the results of one test anyway!

I'm ignoring it, but wish someone would find a fix.

Good luck.

Several updates later, this problem has not gone away.

Has anyone got any suggestions?

This happened to me also. It seems to be a startup/timing issue for me at least.

If I leave windows at the logon prompt after reboot for a minute or so the error dialogue does not appear when logging in. If i reboot and log in as soon as the login prompt appears then the error appears. Very strange!

Hi,

Just to follow up, has the issue been resolved?

Regards.

Check this thread with a similar concern and see if it helps.

Regards.