Question: Does any know how to get the RDP version Windows is running with?

Answer: 
or you could also click Start > Run > mstsc and when you see the Remote Desktop Connection window appear, click the top left hand corner "computer" icon and select "About".
There can be maybe better way with PowerShell.

First one need complete table of MSTSC build numbers and just compare to output of:

```
(Get-Item C:\Windows\System32\mstsc.exe).VersionInfo.FileVersion

```

And the second one is to read CLSID of registered components which contain also RDP binaries, like that:

```
$Current = 0
$GUID = Get-ChildItem -LiteralPath "Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID" | Select Name
$GUIDNum = Get-ChildItem -LiteralPath "Registry::HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID" | Select Name | Measure
While($Current -ne $GUIDNum.Count) {
$Path = $GUID[$Current] | Select -ExpandProperty Name
$GUIDName = ((get-itemproperty -literalpath "Registry::$Path").'(default)') 
If ($GUIDName -like 'Microsoft RDP Client Control (redistributable) - version*')
{
Write-Host $GUIDName
}
$Current++
}

```