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Apr 03 2024, 07:00 AM - 11:00 AM (PDT)
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Microsoft Defender VPN - Android Auto Communication error 21

Iron Contributor



Using Microsoft Defender for Endpoint VPN ( has caused connection issues with Android Auto, (See attached image) and users cannot get it to load. The only way it seems to get this to work is to turn off the VPN which we do not want to do as its an intuned corporate device which we want to have VPN always working on the device for security reasons. Has anyone got any solution?

Users receive the following error:

Communication error 21 - Being connected to a VPN may prevent Android Auto from starting. If you're using a VPN, turn it off and try reconnecting to Android Auto.



2 Replies



I use NordVPN. I had to go into the VPN settings, go to Split Tunneling. You will see a list of your Apps that you can add to Split Tunneling. You will probably notice that Android Auto is not in the list. I had to click on the "three dots" to get to "System Apps". Once I did, Android Auto was available to add to Split Tunneling...  and with Nord, it works half the time. (not happy about this)


Hope this helps...



@Mondas did you resolve this issue and if so how?


Just had this issue reported to me by a user today. The Defender for Android VPN is a simple loopback VPN service used for the web protection service to check for malicious links. I haven't seen anywhere that it can be configured for split tunneling and in anycase I couldn't see how that would impact connections to Android Auto via bluetooth or USB. 

Unfortunately I don't have Android auto in my vehicle to test