Description of problem:
au retour sur mon ordinateur j'ai vu les erreur 

Version-Release number of selected component:
dnf-0.4.19-1.fc20

Additional info:
reporter:       libreport-2.2.1
cmdline:        /usr/bin/python /usr/bin/dnf -v makecache timer
executable:     /usr/bin/dnf
kernel:         3.13.9-200.fc20.x86_64
runlevel:       N 5
type:           Python
uid:            0

Truncated backtrace:
base.py:135:_add_repo_to_sack:RuntimeException: load_yum_repo() failed: 3.

Traceback (most recent call last):
  File "/usr/bin/dnf", line 35, in <module>
    main.user_main(sys.argv[1:], exit_code=True)
  File "/usr/lib/python2.7/site-packages/dnf/cli/main.py", line 242, in user_main
    errcode = main(args)
  File "/usr/lib/python2.7/site-packages/dnf/cli/main.py", line 75, in main
    return _main(base, args)
  File "/usr/lib/python2.7/site-packages/dnf/cli/main.py", line 124, in _main
    cli.run()
  File "/usr/lib/python2.7/site-packages/dnf/cli/cli.py", line 1378, in run
    return self.command.run(self.base.extcmds)
  File "/usr/lib/python2.7/site-packages/dnf/cli/commands/__init__.py", line 683, in run
    self.base.fill_sack() # performs the md sync
  File "/usr/lib/python2.7/site-packages/dnf/base.py", line 217, in fill_sack
    self._add_repo_to_sack(r.id)
  File "/usr/lib/python2.7/site-packages/dnf/base.py", line 135, in _add_repo_to_sack
    load_presto=repo.deltarpm)
RuntimeException: load_yum_repo() failed: 3.

Local variables in innermost frame:
repo: <Repo updates>
hrepo: <_hawkey.Repo object at 0x7f9dfa480ea0>
self: <dnf.cli.cli.BaseCli object at 0x290cad0>
name: 'updates'