Hyper-V - Unable to Create External Virtual Switch

Kari, thx a lot for this solution.
u saved a day again

i cant create external virtual switch
so i use 1. solution
tricked VM with internal switch and sharing options of wifi adapter
thx

Kari said:

Two suggestions. First a safe workaround, then a bit more risky solution which might or might not work.

A safe workaround:

1.) Create an Internal virtual switch

2.) Change your virtual machine Network Adapter to your new Internal switch

Attachment 67939

Kari

i have 6 colleagues in the lab, and i am the only one using hyperV, others using VMware. I'm always happy when prove that HyperV is not garbage

I know this is an old post, but just ran into this problem myself. My fix might help others so here it is :)

Had this issue twice in the last few weeks. First time in the end I decided to reinstall the pc, however the second time I decided to spend some time to try to fix it...

Hyper-V is very sensitive to network changes outside of Hyper-V. Things like "netcfg -d" don't work, and possibly make things even worse. Diagnose/reset network using the Windows troubleshooter might break Hyper-V and vpn and/or antivirus solutions usually hook into network interfaces aswell possibly adding extra issues.

Using Process Monitor I found out that creating an external vSwitch in Hyper-V resulted in multiple access denied results on 1 particular registry key:

HKLM\System\CurrentControlSet\Control\Class\{4D36E972-E325-11CE-BFC1-08002be10318}\Properties

Access to this key is denied by default, I have checked on multiple machines, but for some reason Hyper-V wants to do something here (possibly related to network changes outside Hyper-V).

As a workaround I opened the advanced permissions windows of the parent key (the guid) and checked the "Replace all child object permission entries with inheritable permission entries from this object" and clicked on OK. You might get an error that the permissions could not be set on all keys, but that's ok. If all went well you can now open the Properties key.

After this, I was able to create an external vSwitch again.



Disclaimer: this is a workaround which helped me fix this, however I'm not sure if there any negative side effects to changing the permissions on the Properties key. So don't blame me