F-20: no shutdown/reboot due to unstopped jobs

[antonio montagnani]

when I want to poweroff/reboot the machine I get this message:
  a stop job is running for User Manager for 42
and it takes a very long time to stop

Sometimes I get a similar message for CUPS printing

Any idea??
-- 
Antonio M
Skype: amontag52

Linux Fedora F20 (Heisenbug) on Acer 5720

http://lugsaronno.altervista.org
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