Plesk 12 installation fails on OpenSUSE 13.1 with the error:
===> Checking for the necessary system accounts Checking for the system groups and users necessary for MySQL... Checking for the group ''... Trying to add group ''... groupadd: '' is not a valid group name ERROR while trying to add group ''
Such behavior is considered as software issue, internal ID is PPPM-1833. Root cause is absent syslog package. The issue should be fixed in further Parallels Plesk updates.
To solve the issue install syslog manually before product installation.