It seems the problem is caused by the embedded "KDE- Partitionsverwaltung" (partition manager). When I tried to delete and to make a new (the same) partition using "KDE-Partitionsverwaltung" without installing process an error occurs.
So I started partition magic, gparted created a new partition table and created the partitions again, no error. Since this time no problem by installing the system anymore. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1447600 Title: 15.04 installer hangs in partitioner during something else To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubiquity/+bug/1447600/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs