High CPU usage by "WinHTTP Web Proxy Auto-Discovery Service"

[darkblade]

I have an issue where the Windows "WinHTTP Web Proxy Auto-Discovery Service" consumes high CPU usage.

This occurs when a Wi-Fi card that has an established connection to a network, is disconnected - either switching off Wi-Fi or plugging in an ethernet cable. When this happens, the WinHTTP Web Proxy Auto-Discovery Service starts and consumes ~7% CPU - but this will grow to as much as 100% as applications need to use the internet.

Once the service is in this state - the only way to recover is to reboot.

I can switch between the LAN Wi-Fi to the guest Wi-Fi without issue. Once I have disabled Wi-Fi and rebooted after the "WinHTTP Web Proxy Auto-Discovery" service issue, I can connect and disconnect an ethernet cable without any issue. I've even used a USB to ethernet adaptor and switched between two NICs running on the same laptop with no issue.

The problem seems to be when a Wi-Fi connection is stopped.

I have this issue with a Dell XPS 9560 and Dell M3800 laptops, plus an Asus S200E notebook all running Win 10.
I thought that it might have been something to do with my home network - but I have tried this at another house and the corporate Wi-Fi at work and still get the same issue (although it was a bit more hit and miss on the corporate network).

I've been working with Dell support trying to get this fixed, but I think they are out of their depth. We've tried rolling back drivers, the BIOS etc but nothing makes a difference.

I'm convinced that a Win 10 update is the cause of the issue - which started around mid-late Jan.

Is anyone else able to reproduce this on their kit?

 

[darkblade]

Turns out that this is a bug in Windows that was introduced by the 1709 feature update.

I found a laptop that hadn't been used for a few months, so started installing Windows updates and testing the Wi-Fi disconnect after each update.

No issues until the 1709 update is installed. I am now able to reproduce this on 4 laptops.

Thanks to Microsoft for wasting days of my time testing your enforced updates.

 

[Jamauk]

Do Microsoft actually test their updates before releasing them to the general public? There seems to be loads of threads mainly since the launch of Windows 10 with issues in updates, almost like fix one issue, introduce another. Although saying that, Apple haven't done so well recently.