Hi Marc,
Are you connecting to head node or the compute node? some error message seems from head node, and some from compute node. If you run the command in a on-premise client machine, you will need to install a certificate in the Current User\Trusted Root Certification
Authorities. During the deployment, the iaas deployment script will install the certificate temporarily, and will remove it immediately when the deployment completed.
You can use the following powershell script to fetch the certificate:
$ServiceName = "servicename"
$VMName = "vmname"
$cerSavePath = "d:\myheadnode.cer"
$vm = Get-AzureVM -ServiceName $ServiceName -Name $VMName
$winRmCertificateThumbprint = $vm.VM.DefaultWinRMCertificateThumbprint
$winRmCertificate = Get-AzureCertificate -ServiceName $ServiceName -Thumbprint $winRmCertificateThumbprint -ThumbprintAlgorithm sha1
$certBytes = [System.Convert]::FromBase64String($winRmCertificate.Data)
[IO.File]::WriteAllBytes($cerSavePath, $certBytes)