New installation of MP2 A4 fails on Win 8.1 x64 with error: "String cannot be of zero length" (1 Viewer)

[SplatAttack]

Client/server installation previous running MP1. Other clients still working on MP1. Installed MP2 server alongside MP1 server. Ran a complete uninstall of MP1 client on this PC. Ran MP2 setup: Background Dos screen, Welcome screen, License screen, click on Client only, click on install, please wait screen, Windows UAC screen, error message "MediaPortal 2 Setup Wizard ended prematurely", click on Finish. Log attached.