I am having issues setting up OpenSSH for Windows, using public key authentication.
I have this working on my local desktop and can ssh with a key from Unix machines
I have solved the issue...
It is related to the account that started the service - it was using the Local System account - this was stopping it accessing the public key and authorized_keys file.
Once I stopped the service and started as the user I was trying to connect into, it worked!
So basically, you need to start with a service account and then external users connect in as that user.