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I have Kubuntu 13.04 (unsupported release), and want to upgrade it to 14.04. When I'm trying to run do-release-upgrade I got this error:

Traceback (most recent call last): File "/usr/bin/do-release-upgrade", line 123, in "%(url)s\n") % { 'url' : url }) ValueError: unsupported format character '?' (0xa) at index 55

I know that I should upgrade to 13.10 first. I read the documentation, but when I tried to add old-releases repository to my sources list, something like deb raring main restricted universe multiverse I get 404 error while updating my sources.

Is this documentation too old to help me? Where can I find newer docs? Or can you show me other way to upgrade my OS?

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Edit /usr/bin/do-release-upgrade and comment out lines 123 - 127

# make sure to inform the user if his distro is no longer supported
# this will make it appear in motd (that calls do-release-upgrade in
#  check-new-release mode)
#  if m.no_longer_supported is not None:
#    url = ""
#    print(_("Your Ubuntu release is not supported anymore."))
#    print(_("For upgrade information, please visit:\n"
#            "%(url)s\n") % { 'url' : url })

Make sure to remove comments after upgrade!

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Thank you! Allowed me to get from 13.04 to 13.10 (the old-releases trick) and now to 14.04 :) – jaywink Aug 6 '14 at 17:07

Not an official tutorial, but worked successfully for me with lubuntu.

1. Change /etc/apt/sources.list to a 13.10 repository
(use the list generator from

2. apt-get update && apt-get upgrade && reboot && apt-get dist-upgrade
(will upgrade to 13.10. Don't panik if your desktop is lost. Solve this by clearing desktop configs in your /home/userxxx and re-login)

3. reboot (just in case)

4. start the software updater and run the 14.04 LTS upgrade

5. Your're done.

May take quite a bit of time (2 dist upgrades) and is not guaranteed to
work in every situation, but if not, re-installing is still an option.

share|improve this answer

I recommend a new/clean install of 14.04 LTS.

You might be able to upgrade to 13.10 by having that on other media (eg. USB stick).

But there is no support (past Jan-2014) for 13.04, for any issue that might occur.

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