Machine Name

[SomethinCool]

I am trying to get the machine name of the computer that is running my application but i keep getting this error (it's on the line that is in bold):

Object reference not set to an instance of an object.

Private Sub Form4_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        AxAnimation1.Open(Application.StartupPath & "\EARTH_SPIN.avi")
        MachineName = Space$(64)
        CompNameSize = Len(MachineName)
        [B]Compname = GetComputerName(MachineName, CompNameSize)[/B]
        Compname = Trim(MachineName)
        Label1.Text = Compname
    End Sub

It looks like i needed to declare somethin....i think. Does anyone see a problem?