[DllImport("shlwapi.dll", EntryPoint = "PathFileExistsW",  SetLastError = true, CharSet = CharSet.Unicode)]

static extern bool PathFileExists([MarshalAs(UnmanagedType.LPTStr)]string pszPath);

<DllImport("shlwapi.dll", EntryPoint:="PathFileExistsW",  SetLastError:=True, CharSet:=CharSet.Unicode)> _

Public Function PathFileExists(<MarshalAs(UnmanagedType.LPTStr)>pszPath As String) As <MarshalAs(UnmanagedType.Bool)> Boolean

Public Declare Function PathFileExists Lib "shlwapi" Alias "PathFileExistsA" _