ora-01005: null password given, logon denied

[Eric Strybos]

Hi,

I'm new to vb.net, but i follow the guide "Microsoft
visual basic.net step by step" from Michael Halvorson.
I attend to make a little exercise of connecting to Oracle
database 8.1.7.
I made a simple form with a textbox connected to a dataset
and a button to load the data into.

Private Sub Button1_Click(ByVal sender As System.Object,
ByVal e As System.EventArgs) Handles Button1.Click
dsBusinessUnit.Clear()
Try
OleDbDataAdapter1.Fill(dsBusinessUnit)
Catch
MsgBox(Err.Description)
End Try

End Sub

BUT ... I receive always the following errormessage while
executing the instruction : OleDbDataAdapter1.Fill
(dsBusinessUnit)

ora-01005: null password given, logon denied
This message appears while testing it with the 2 available
providers i.e. "Oracle Provider for OLEDB" and "Microsoft
OLE DB Provider for Oracle"

When i test my connection with the data adapter preview, i
can fill the appropriate dataset with data.

I use the the Microsoft .NET Framework 1.1.

Can somebody help me ?

Thanks in advance

Eric