I have just tried to upgrade to 13.10 from 13.04 and I have received the following error in console

Checking for a new Ubuntu release

authenticate 'saucy.tar.gz' against 'saucy.tar.gz.gpg' 

extracting 'saucy.tar.gz'

Traceback (most recent call last):

  File "/tmp/user/0/ubuntu-release-upgrader-xnzjbd/saucy", line 10, in <module>

    sys.exit(main())

  File "/tmp/user/0/ubuntu-release-upgrader-xnzjbd/DistUpgrade/DistUpgradeMain.py", line 240, in main

    save_system_state(logdir)

  File "/tmp/user/0/ubuntu-release-upgrader-xnzjbd/DistUpgrade/DistUpgradeMain.py", line 133, in save_system_state

    scrub_sources=True)

  File "/tmp/user/0/ubuntu-release-upgrader-xnzjbd/DistUpgrade/apt_clone.py", line 149, in save_state

    self._write_state_sources_list(tar, scrub_sources)

  File "/tmp/user/0/ubuntu-release-upgrader-xnzjbd/DistUpgrade/apt_clone.py", line 241, in _write_state_sources_list

    "./etc/apt/sources.list.d/"+source)

  File "/tmp/user/0/ubuntu-release-upgrader-xnzjbd/DistUpgrade/apt_clone.py", line 246, in _add_file_to_tar_with_password_check

    for line in f.readlines():

  File "/usr/lib/python2.7/codecs.py", line 296, in decode

    (result, consumed) = self._buffer_decode(data, self.errors, final)

UnicodeDecodeError: 'utf8' codec can't decode byte 0x9f in position 3: invalid start byte

This is in what I get in update-manager gui

do-release-upgrade crashed on UnicodeDecodeError in decode(): 'utf8' codec can't decode byte 0x9f in position 3 : invalid state