The log has errors like boltd[712]: /usr/libexec/boltd: symbol lookup error: /usr/libexec/boltd: undefined symbol: g_log_structured_standard
could you share the output of $ ldd -r /usr/libexec/boltd it sounds like an old version of glib has been installed taking of the ubuntu version? ** Changed in: modemmanager (Ubuntu) Status: Confirmed => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1961859 Title: When we install ModemManager1.16.6 and others, this will lead to ubuntu can not enter into GNOME UI. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/modemmanager/+bug/1961859/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs