Damit es hier nicht zu Problemen kommt, weist Blizzard darauf hin dass vor der Installation der Liveversion sämtliche Dateien der Diablo 3 Beta zu entfernen sind:
If you have installed the Diablo III beta at any point and intend to install Diablo III, please make sure that all Diablo III beta files are removed from your system prior to installing the full game.
This includes the Battle.net folder, which can be found in the following locations:
[WINDOWS XP]
C:\Documents and Settings\All Users\Application Data\Battle.net
[WINDOWS VISTA/7]
C:\ProgramData\Battle.net
MAC
/Users/Shared/Battle.net
Once this folder and all other beta files are removed, simply run the installer again.
mfg und danke an diii.de für die Info