Powershell Suppress Certificate Notification - powershell

Question

I am writing a script to connect from a Windows 10 Client to a Terminal Server with the RDP-Protocoll.
The thought behind is: On these ThinClients we have about 20 RDP-Files. With about 10 of them, the password needs to be safed.
So it is quite a lot of work if you always have to save the password on every new ThinClient.
But I thought I could solve this problem with a powershell script. I just have to open the connection 1 time successfully and save the credentials and further on the credentials are saved.
I will show my code first:
$Server = "xx.yy.zz.xx"
$User = "DOMAIN\User"
$password = "password"
cmdkey /generic:"$Server" /user:"$User" /pass:"$password"
mstsc /v:"$Server"
This works so far.
But I always get the this Notification:
This is a Symbol-Picture from the Internet, as my Notification is in German. It is exactly the same, just easier to understand.
Even if I install the certificate, the notification keeps popping up.
How can I check the field with Powershell, where it says Don't ask me again for connections to this computer?

Answer 1

Ok i found a solution!
There is a registry-Key generated when you Tick "Dont ask me again..."
Now i just added the necessary Registry Keys with my Powershell Script..
function Test-RegistryValue {
param (
[parameter(Mandatory=$true)]
[ValidateNotNullOrEmpty()]$Path,
[parameter(Mandatory=$true)]
[ValidateNotNullOrEmpty()]$Value
)
try{
Get-ItemProperty -Path $Path | Select-Object -ExpandProperty $Value -ErrorAction Stop | Out-Null
return $true
}
catch{
return $false
}
}
#Certificate warning turn off
$exists = Test-RegistryValue -Path 'HKCU:\Software\Microsoft\Terminal Server Client' -Value 'AuthenticationLevelOverride'
if($exists -eq $False){
reg add "HKEY_CURRENT_USER\Software\Microsoft\Terminal Server Client" /v "AuthenticationLevelOverride" /t "REG_DWORD" /d 0 /f
}
Like this it works without this certificate notification!