HTC updated the installer and the Sync Manager, but it is not working.
During the installation, the installer is giving an error message, that the driver package can not be installed and it is asking, that we would like to continue with installation of sync manager... So, the 1.1.48 version is wrong.
But I found a workaround: You have to install first the older sync manager: 188.8.131.52 and then you have to update it to the newest 1.1.48.
The old version will install a HTC Driver version 3.0.0.024. During the update the error message appear, but you have already installed the drivers, so you can continue. With that workaround I have working the tethering and the sync maneger too.