SNMP Exception : data construction exception

[antoheb]

Here is my function in the code below and also the exception message. I basically want to do a walk operation on a snmp device. My problem is when I call this function on a OID with only one value, the walk operation returns me the value I want. But when I tried to call my function on a OID table, this exception is always thrown. It looks like the walk operation cannot build my list of variable when mutliple variable exists.

************* My Function *****************
private void walk_snmp(VersionCode snmpVersion, String ipAddress, Int32 port, String communityString, String OID)
{
var results = new List();
Messenger.BulkWalk(snmpVersion,
new IPEndPoint(IPAddress.Parse(ipAddress), port),
new OctetString(communityString),
null,
new ObjectIdentifier(OID),
results,
20000,
10,
WalkMode.WithinSubtree,
null,
null);

foreach (Variable result in results)
{
    this.operationInfoBox.Text = "OID : " + result.Id.ToString() + " Result = " + result.Data.ToString() + "\n";
}

}

************** Exception Text **************
Lextm.SharpSnmpLib.SnmpException: data construction exception ---> System.ArgumentException: Invalid varbind data length: 1.
Parameter name: varbindSection
at Lextm.SharpSnmpLib.Variable.Transform(Sequence varbindSection)
at Lextm.SharpSnmpLib.ResponsePdu..ctor(Tuple2 length, Stream stream) at Lextm.SharpSnmpLib.DataFactory.CreateSnmpData(Int32 type, Stream stream) --- End of inner exception stack trace --- at Lextm.SharpSnmpLib.DataFactory.CreateSnmpData(Int32 type, Stream stream) at Lextm.SharpSnmpLib.DataFactory.CreateSnmpData(Stream stream) at Lextm.SharpSnmpLib.Sequence..ctor(Tuple2 length, Stream stream)
at Lextm.SharpSnmpLib.DataFactory.CreateSnmpData(Int32 type, Stream stream)
at Lextm.SharpSnmpLib.Messaging.MessageFactory.ParseMessage(Int32 first, Stream stream, UserRegistry registry)
at Lextm.SharpSnmpLib.Messaging.MessageFactory.ParseMessages(Byte[] buffer, Int32 index, Int32 length, UserRegistry registry)
at Lextm.SharpSnmpLib.Messaging.SnmpMessageExtension.GetResponse(ISnmpMessage request, Int32 timeout, IPEndPoint receiver, UserRegistry registry, Socket udpSocket)
at Lextm.SharpSnmpLib.Messaging.SnmpMessageExtension.GetResponse(ISnmpMessage request, Int32 timeout, IPEndPoint receiver, Socket udpSocket)
at Lextm.SharpSnmpLib.Messaging.SnmpMessageExtension.GetResponse(ISnmpMessage request, Int32 timeout, IPEndPoint receiver)
at Lextm.SharpSnmpLib.Messaging.Messenger.BulkHasNext(VersionCode version, IPEndPoint receiver, OctetString community, OctetString contextName, Variable seed, Int32 timeout, Int32 maxRepetitions, IList1& next, IPrivacyProvider privacy, ISnmpMessage& report) at Lextm.SharpSnmpLib.Messaging.Messenger.BulkWalk(VersionCode version, IPEndPoint endpoint, OctetString community, OctetString contextName, ObjectIdentifier table, IList1 list, Int32 timeout, Int32 maxRepetitions, WalkMode mode, IPrivacyProvider privacy, ISnmpMessage report)
at snmp_agent.Form1.walk_snmp(VersionCode snmpVersion, String ipAddress, Int32 port, String communityString, String OID)
at snmp_agent.Form1.submitBtn_click(Object sender, EventArgs e)
at System.Windows.Forms.Control.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ButtonBase.WndProc(Message& m)
at System.Windows.Forms.Button.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)