yes you do.
i had problems with htc sync - my computer wouldnt recognise the fact it was connected.
what i did:
1. uninstall htc sync AND driver.
2. re-install the latest version on htc website.
3. connect usb cable (at this point it should connect if its working), if not...
4. switch phone off and then on again (without removing usb cable)
5. give it a minute or two and the sync notification icon should appear.
6. off you go and install update!
i dont really need htc sync and wasn't bothered that it didnt work but you do need it for update.