Thought i did the downgrade correctly, but can't connect.

Is there a way to verify? I have s:i730.2.6V.YH25

When I try to USB tether, I get "Dialing #777...then *99#... then Error 668, sometimes Error 692.

I do have upath changed to data (usb modem), & have read all this thread and the "VZW WM5 tethering does not work!" thread. Haven't changed anything on laptop, but software add to update/downgrade phone. Worked fine before wm5/phone upgrade.

Any helps would be greatly apprecated.