NC25 - Update and fresh installation Problem

Hi,

i tried to upgrade from 24.0.7 to 25 yesterday. after upgrade i got a blank screen. so i deleted the theming app, but then i got several error messages. i was really angry, so i decided to try a new installation of nc25. i copied the files to my shared hosts, dropped the tables in the database and startet the installaton wizzard. now i cannot connect to the database. the credentials are right - i didn´t changed it.

is there any possibility to install nc25 otherwise?