I have BB8820 with tethering service, full data, package, the works. I have installed desktop manager and device manager. 4.6.0.12

I have viewed the documents posted on BB forums and have set up my BB, my modem, all applicable settings. I dial up, get a connection, accepts UN and PW, BUT I get the error stated in the title of this thread.

Can anyone help? I have tried several times to re-do the steps but to no avail. I have windows vista OS.

THANK YOU