I have this simple line of code:

```
var entry = new DirectoryEntry("WinNT://DOMAIN/MachineName, Computer");
Console.WriteLine(entry.Guid);

```

In reality, the path is supplied by command line. This simple Console App is compiled for testing and in my tests I find that:

* Connecting to my own Windows 7 PC works.
* Connecting to any other Windows XP machine on the network, works.
* Connecting to any other Windows 7 machines on the network fails with:

> 
> Unhandled Exception: System.IO.FileNotFoundException: The network path was not found.
> 
> 
> at System.DirectoryServices.Interop.UnsafeNativeMethods.IAds.GetInfo()
>  at System.DirectoryServices.DirectoryEntry.RefreshCache()
>  at System.DirectoryServices.DirectoryEntry.FillCache(String propertyName)
>  at System.DirectoryServices.DirectoryEntry.get\_NativeGuid()
>  at System.DirectoryServices.DirectoryEntry.get\_Guid()
>  at GetDirectoryEntryProperties.Program.Main(String[] args) in D:\GetDirectoryEntryProperties\Program.cs:line 15
> 
> 
> 

Any ideas?

I am an administrator on all machines, however I did have another issue caused by a Device Lock service which caused an `UnauthorizedAccessException` on interrogation, but in this case I can't even read the Guid of the machine.

Event Log is showing nothing of use.

Luke