Error when editing node after adding via SDK/API

After adding a node to Solarwinds via SDK or API (I'm using Powershell) I cannot edit the node settings. I get the following error:

I have tried:

Rebooting the Solarwinds box

Adding the node with the absolute bare minimum properties required to create a new node

Rebooting the server that's being monitored

One of the things I read to try was to add a custom property name and then remove it.

The command I am using looks like this:

$newNodeProps = @{  IPAddress = $ipaddress  EngineID = 1  ObjectSubType = "WMI"  DNS = ""  SysName = ""
}

#region CREATING the node
$newNodeUri = New-SwisObject $swis -EntityType 'Orion.Nodes' -Properties $newNodeProps

If you require more information please let me know.