Remote Desktop Connection An internal error has occurred.

RDP Error Message:

Resolution:

Method 1: Create and apply a self signed certificate on the server

$fqdn=$env:computername+$(if($env:USERDNSDOMAIN){'.'+$env:USERDNSDOMAIN})
$newCertificate=New-SelfSignedCertificate -certstorelocation cert:\localmachine\my -dnsname $fqdn
$thumbPrint=$newCertificate.Thumbprint
wmic /namespace:\\root\CIMV2\TerminalServices PATH Win32_TSGeneralSetting Set SSLCertificateSHA1Hash=$thumbPrint

Method 2: install an alternate RDP client

Method 3: fix firewall issues