1. Make the following registry changes:
HKLM\Software\OEM\WMODEM
add DWORD "CheckProfile"=0
set DWORD "Multi-NAI"=0
set DWORD "WModemDUN"=0
2. Start Modem Link (Open then select "Start" from the menu) with data disconnected and USB unplugged.
3. Connect USB. Windows will automatically download and install the appropriate drivers (you may have to click through some UAC prompts first to confirm).
4. Set up a new dialup connection using HTC USB Modem. Number is #777, user name is your
phone number, and password is "vzw" without the quotes.