GetTokenInformation returns invalid SID? - vb.net

Question

While following this i ran into a problem.
<DllImport("advapi32.dll", SetLastError:=True)> _
Private Shared Function OpenProcessToken(ByVal ProcessHandle As IntPtr, ByVal DesiredAccess As Integer, ByRef TokenHandle As IntPtr) As Boolean
End Function
<DllImport("advapi32.dll", SetLastError:=True)> _
Private Shared Function GetTokenInformation(TokenHandle As IntPtr, TokenInformationClass As TOKEN_INFORMATION_CLASS, TokenInformation As IntPtr, TokenInformationLength As UInteger, ByRef ReturnLength As UInteger) As Boolean
End Function
<DllImport("advapi32.dll", SetLastError:=True)> _
Private Shared Function IsValidSid(SID As Byte()) As Boolean
End Function
For Each p As Process In Process.GetProcesses
Dim processHandle As IntPtr = OpenProcess(PROCESS_QUERY_LIMITED_INFORMATION, False, p.Id)
If Not processHandle = Nothing Then
Dim tokenhandle As IntPtr = Nothing
Dim bool As Boolean = OpenProcessToken(processHandle, TOKEN_READ, tokenhandle)
If bool = False Then
Dim win32error As String = New Win32Exception(Marshal.GetLastWin32Error).Message
MessageBox.Show(win32error)
Else
Dim sidlength As UInteger = Nothing
Dim SIDbyte As Byte() = Nothing
Dim somebool As Boolean = GetTokenInformation(tokenhandle, TOKEN_INFORMATION_CLASS.TokenUser, Nothing, 0, sidlength)
If Not somebool Then
Dim win32error As String = New Win32Exception(Marshal.GetLastWin32Error).Message
MessageBox.Show(win32error)
''RETURNS "The data area passed to a system call is too small" error.
End If
ReDim SIDbyte(35) '' I hardcoded '35' because it's what i'm getting with sidlength.
somebool = GetTokenInformation(tokenhandle, TOKEN_INFORMATION_CLASS.TokenUser, SIDbyte, SIDbyte.Length, sidlength)
''RETURNS TRUE THE SECOND TIME.
If Not somebool Then
Dim win32error As String = New Win32Exception(Marshal.GetLastWin32Error).Message
MessageBox.Show(win32error)
End If
If IsValidSid(SIDbyte) Then
MessageBox.Show("Valid")
Else
MessageBox.Show("Not Valid")
End If
''RETURNS INVALID SID. (FAILS)
The first call to GetTokenInformation fails as it's supposed to i guess... returning "sidlength" with value of 36.
Second call succeeds and SID Byte() gets populated, but the call to "IsValidSID" Returns false... and i can't figure out why, if the SIDbytes are populated successfully, what's the problem?