Comment 48 for bug 1053910

I've tried, but it doesn't change anything.
Maybe because it's a separate thread?

Problem is happening in File "/usr/lib/python2.7/dist-packages/UpdateManager/Core/MetaRelease.py", line 262
So the exception was caught by /usr/lib/python2.7/socket.py
socket.error: [Errno 104] Connection reset by peer

python -m trace -c -t /usr/share/kde4/apps/muon-notifier/releasechecker
MetaRelease.py(160): try:
MetaRelease.py(161): if os.path.getsize(self.METARELEASE_FILE) == 0:
 --- modulename: genericpath, funcname: getsize
genericpath.py(49): return os.stat(filename).st_size
MetaRelease.py(165): return True
MetaRelease.py(137): thread.start_new_thread(self.download, ())
releasechecker(35): while metaRelease.downloading:
releasechecker(36): time.sleep(1)
Unhandled exception in thread started by <bound method MetaReleaseCore.download of <UpdateManager.Core.MetaRelease.MetaReleaseCore object at 0x1a44fd0>>
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/UpdateManager/Core/MetaRelease.py", line 262, in download
    uri=urllib2.urlopen(req, timeout=20)
  File "/usr/lib/python2.7/urllib2.py", line 126, in urlopen
    return _opener.open(url, data, timeout)
  File "/usr/lib/python2.7/urllib2.py", line 400, in open
    response = self._open(req, data)
  File "/usr/lib/python2.7/urllib2.py", line 418, in _open
    '_open', req)
  File "/usr/lib/python2.7/urllib2.py", line 378, in _call_chain
    result = func(*args)
  File "/usr/lib/python2.7/urllib2.py", line 1207, in http_open
    return self.do_open(httplib.HTTPConnection, req)
  File "/usr/lib/python2.7/urllib2.py", line 1180, in do_open
    r = h.getresponse(buffering=True)
  File "/usr/lib/python2.7/httplib.py", line 1030, in getresponse
    response.begin()
  File "/usr/lib/python2.7/httplib.py", line 407, in begin
    version, status, reason = self._read_status()
  File "/usr/lib/python2.7/httplib.py", line 365, in _read_status
    line = self.fp.readline()
  File "/usr/lib/python2.7/socket.py", line 447, in readline
    data = self._sock.recv(self._rbufsize)
socket.error: [Errno 104] Connection reset by peer
releasechecker(35): while metaRelease.downloading:
releasechecker(36): time.sleep(1)
releasechecker(35): while metaRelease.downloading:
releasechecker(36): time.sleep(1)
releasechecker(35): while metaRelease.downloading:
releasechecker(36): time.sleep(1)

So basically script is ignoring 'Unhandled exception' and script is continuing to check the release every second.

Something similar which I found:
http://askubuntu.com/questions/130267/cant-update-to-ubuntu-12-04-on-11-10