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This will list all GUIDs related to Dnscache, which you can use in your $RegistryPath.
Sample Powershell Output
A sample Powershell output when running the following commands:
1. Get-NetAdapter | Select-Object Name, InterfaceGuid
2. Get-ChildItem -Path "HKLM:\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces" | Select-Object PSChildName
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