Comment 3 for bug 794518

Exception during installation:
Jun 8 11:28:57 ubuntu plugininstall.py: Traceback (most recent call last):
Jun 8 11:28:57 ubuntu plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 1547, in <module>
Jun 8 11:28:57 ubuntu plugininstall.py: install.run()
Jun 8 11:28:57 ubuntu plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 56, in wrapper
Jun 8 11:28:57 ubuntu plugininstall.py: func(self)
Jun 8 11:28:57 ubuntu plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 208, in run
Jun 8 11:28:57 ubuntu plugininstall.py: self.remove_extras()
Jun 8 11:28:57 ubuntu plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 1303, in remove_extras
Jun 8 11:28:57 ubuntu plugininstall.py: self.do_remove(regular)
Jun 8 11:28:57 ubuntu plugininstall.py: File "/usr/share/ubiquity/plugininstall.py", line 923, in do_remove
Jun 8 11:28:57 ubuntu plugininstall.py: if not cache.commit(fetchprogress, installprogress):
Jun 8 11:28:57 ubuntu plugininstall.py: File "/usr/lib/python2.7/dist-packages/apt/deprecation.py", line 98, in deprecated_function
Jun 8 11:28:57 ubuntu plugininstall.py: return func(*args, **kwds)
Jun 8 11:28:57 ubuntu plugininstall.py: File "/usr/lib/python2.7/dist-packages/apt/cache.py", line 433, in commit
Jun 8 11:28:57 ubuntu plugininstall.py: res = self._fetch_archives(fetcher, pm)
Jun 8 11:28:57 ubuntu plugininstall.py: File "/usr/lib/python2.7/dist-packages/apt/cache.py", line 279, in _fetch_archives
Jun 8 11:28:57 ubuntu plugininstall.py: raise LockFailedException("Failed to lock %s" % lockfile)
Jun 8 11:28:57 ubuntu plugininstall.py: LockFailedException: Failed to lock /target/var/cache/apt/archives/lock
Jun 8 11:28:57 ubuntu plugininstall.py: