Question : Finding file owner - getting an error: identity references could not be translated

Using VS 2005 - I was scanning user shares and this code was working fine.
Altered it to departmental shares and I'm getting the error:
Some or all identity references could not be translated.

Any ideas? Just trying to find the owner account of the file in question - if there's another/better way, I'm open to trying different solutions.
Thanks

         
          For Each fi In aDir.GetFiles()
  Dim Owner As NTAccount = CType(fi.GetAccessControl.GetOwner(GetType(NTAccount)), NTAccount)

Answer : Finding file owner - getting an error: identity references could not be translated

Dang! I didn't finish the example before accidently clicking submit

                       
             For Each fi In aDir.GetFiles()
  Try
    Dim Owner As NTAccount = CType(fi.GetAccessControl.GetOwner(GetType(NTAccount)), NTAccount)
  Catch
    Dim Sid as SecurityIdentifier = Ctype(fi.GetAccessControl.GetOwner(GetType(SecurityIdentifier )), SecurityIdentifier )
  End Try