Could not upgrade to lucid: unresolvable problem occurred while calculating the upgrade (python-apt releated?)

[Gavin Panella]

Binary package hint: update-manager

I have tried disabling all 3rd party sources and removing the related packages without luck, then purged all removed packages, still no luck, then purged openoffice.org-help-en-us (on a vague whim after reading bug 181762), but again no luck.

ProblemType: Bug
Architecture: amd64
Date: Sun Mar 28 22:36:35 2010
DistroRelease: Ubuntu 9.10
NonfreeKernelModules: vboxnetflt vboxnetadp vboxdrv nvidia
Package: update-manager 1:0.126.9
PackageArchitecture: all
ProcEnviron:
 PATH=(custom, user)
 LANG=en_GB.UTF-8
 SHELL=bash
ProcVersionSignature: Ubuntu 2.6.31-20.58-generic
SourcePackage: update-manager
Uname: Linux 2.6.31-20-generic x86_64

[Michael Vogt (mvo)]

Thanks for your bugreport.

It looks like its failing because python-apt can not be upgraded for some reason. Could you please give me the output of
$ apt-cache policy python-apt
?

[Gavin Panella (allenap)]

I re-enabled my custom sources this morning so I could get launchpad-developer-dependencies back on this machine again, and I noticed that it didn't automatically select python-apt for upgrade (though it did appear as an available upgrade).

Here's `apt-cache policy python-apt` with the Launchpad PPA in place (I had downgraded python-apt before commencing the release upgrade):

python-apt:
  Installed: 0.7.13.2ubuntu4
  Candidate: 0.7.13.2ubuntu4.1launchpad1
  Package pin: 0.7.13.2ubuntu4.1launchpad1
  Version table:
     0.7.13.2ubuntu4.1launchpad1 600
        500 http://ppa.launchpad.net karmic/main Packages
 *** 0.7.13.2ubuntu4 600
        500 http://gb.archive.ubuntu.com karmic/main Packages
        100 /var/lib/dpkg/status

With the Launchpad PPA disabled I get:

python-apt:
  Installed: 0.7.13.2ubuntu4
  Candidate: 0.7.13.2ubuntu4
  Package pin: (not found)
  Version table:
 *** 0.7.13.2ubuntu4 600
        500 http://gb.archive.ubuntu.com karmic/main Packages
        100 /var/lib/dpkg/status

[Gavin Panella (allenap)]

I have made progress on this by purging ubuntu-desktop (no other packages were uninstalled at the same time) and then removing software-center (then something *aptdaemon*ish went away too). It's now offering to upgrade.

[Gavin Panella (allenap)]

The upgrade completed successfully. The ubuntu-desktop package was automatically reinstalled (marked as partially installed then finished the next time I ran aptitude update) which pulled software-center back in too.

[Launchpad Janitor (janitor)]

[Expired for update-manager (Ubuntu) because there has been no activity for 60 days.]