Connecting VB Excel macro to HP ALM QC11.52

Hi 

I had developed excel macro in QC 10 and was working fine,recently we migrated to QC 11.52 , now it showing some error.

I think im not able to login  itself.  Below is my old code .Commented line is new  address for HPQC 11.52  but is not working giving run time automation error .. do we have to add any new refernce?

Sub OpenQC(Prj)
 'On Error GoTo Err1:

Set QCConnection = CreateObject("TDApiOle80.TDConnection")
QCConnection.InitConnectionEx "http://qualitycenter.nielsen.com/qcbin"
'QCConnection.InitConnectionEx "http://prod.qualitycenter1152.nielsen.com:8080/qcbin"
QCConnection.Login id, pwd
QCConnection.Connect "WATCH", Prj
Set ConnectToQC = QCConnection
If (QCConnection.LoggedIn = True) Then
MsgBox "QC Ok"
Else
MsgBox "Invalid-  Id or  Password"
Exit Sub

End If