[libvirt-users] libvirtd not starting

Hi everybody, I've set up an new CentOS 7.6.1810 server. Then, via yum I installed qemu-kvm libvirt libvirt-python libguestfs-tools virt-install. There were no problems. But when I try to systemctl start libvirtd I get the following message: "libvirtd: process 472: arguments to dbus_message_iter_append_basic() were incorrect, assertion "_dbus_check_is_valid_utf8 (*string_p)" failed in file ../../dbus/dbus-message.c line 2754." Starting libvirtd manually just by issuing the command "libvirtd" without any further arguments is working, though. I do not have the slightest idea what is going on, especially as I didn't change anything about the config files. Any help would be appreciated, thank you Lothar Schilling