Windows Defender SmartScreen Can't be Reached

[caperailfan]

I just installed Windows 10 1803 on a test device, after installing Endpoint Protection Cloud version 22.14.0.54, I am finding Windows Defender SmartScreen can't be reached with the Default Symantec Security Policy applied. Not sure why this is happening, looking at the firewall rules that are configured by the default policy, it doesn't look like the traffic should be blocked.

 

 

[caperailfan]

Interestingly, it looks like this issue resolved itself with time. I can see in the logs that at the time the Firefox installer was luanched, Windows Defender SmartScreen was allowed network access. What I haven't quite figured out yet is why after bing allowed network access, it took a few restarts and an hour or two before being able to access the service. I ahve now seen this behavior on three different devices with Windows 10 version 1803.

On system startup Windows Defender Security Center has a red marker in the system tray. It appears in this version it is unable to determine the security status with Endpoint Protection installed. Not sure if this is the intended or expected behavior.

 

 

[Matt Talaga]

I am having the same issue with Windows 10 1703.  Downloaded a webex exe for a meeting today, and each time I tried to run it, I received a prompt stating SmartScreen can't be reached right now.  Check your Internet connection. Windows Defender SmartScreen is unreachable and can't help you decide if this app is ok to run.

My internet connection works fine, so something must be blocking it.  I'm guessing Symantec Endpoint Protection, but I have not been able to verify.

 

Matt

[Apathetic Realist]

This isn't limited to Symantec. I received a new PC with McAfee pre-installed. While I was setting up the PC and before I stripped off McAfee and replaced it with SEPC, I received the same message.