Short after upgrade, Synaptic failed to open but apt-get still works

[Tony Janssen]

Following screen pops up when opening synaptics (sudo) : application will close when confirming dialog box

E: The value 'natty-proposed' is invalid for APT::Default-Release as such a release is not available in the sources
E: _cache->open() failed, please report.

Where can natty-proposed be disabled as default release, tried purging several locations in older posts without success.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: synaptic 0.75.2ubuntu6
ProcVersionSignature: Ubuntu 3.0.0-10.16-generic 3.0.4
Uname: Linux 3.0.0-10-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
Date: Mon Sep 5 23:52:54 2011
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release amd64 (20101007)
ProcEnviron:
 SHELL=/bin/bash
 PATH=(custom, no user)
 LANG=fr_BE.UTF-8
SourcePackage: synaptic
UpgradeStatus: Upgraded to oneiric on 2011-09-02 (3 days ago)

[3t0g0 (freetogo)]

By adding the dummy "natty" repo back into sources.list shall fix the problem temporarily

[yohjiubuntu-tv:~]$ cat /etc/apt/sources.list
deb http://tw.archive.ubuntu.com/ubuntu natty main universe restricted multiverse

[Adam Delman (flyn-flyn)]

I think this is related to the setting of "Prefer versions from" under Settings->Preferences->Distribution.
Might be worth it to run strace on Synaptic to see where it's reading the setting from.

[Adam Delman (flyn-flyn)]

I've traced this issue to a value in /root/.synaptic/synaptic.conf :

Synaptic "" {
  ViewMode "3";
  showWelcomeDialog "0";
  LastSearchType "1";
  closeZvt "true";
  vpanedPos "214";
  hpanedPos "152";
  windowWidth "1280";
  windowHeight "947";
  windowX "0";
  windowY "30";
  ToolbarState "2";
  Maximized "1";
  Install-Recommends "1";
  AskForUpdateAfterSrcChange "0";
  update "" {
    last "1316901731";
    type "0";
  };

  ShowAllPkgInfoInMain "true";
  AskRelated "true";
  OneClickOnStatusActions "false";
  delAction "3";
  upgradeType "1";
  undoStackSize "20";
  UseTerminal "false";
  AskQuitOnProceed "false";
  useUserFont "0";
  useUserTerminalFont "0";
  statusColumnPos "0";
  statusColumnVisible "1";
  supportedColumnPos "1";
  supportedColumnVisible "1";
  nameColumnPos "2";
  nameColumnVisible "1";
  sectionColumnPos "3";
  sectionColumnVisible "0";
  componentColumnPos "4";
  componentColumnVisible "0";
  instVerColumnPos "5";
  instVerColumnVisible "1";
  availVerColumnPos "6";
  availVerColumnVisible "1";
  instSizeColumnPos "7";
  instSizeColumnVisible "1";
  downloadSizeColumnPos "8";
  downloadSizeColumnVisible "0";
  descrColumnPos "9";
  descrColumnVisible "1";
  color-install "#8A8AE2E23434";
  color-reinstall "#4E4E9A9A0606";
  color-upgrade "#FCFCE9E94F4F";
  color-downgrade "#ADAD7F7FA8A8";
  color-remove "#EFEF29292929";
  color-purge "#A4A400000000";
  color-available "";
  color-available-locked "#A4A400000000";
  color-installed-updated "";
  color-installed-outdated "";
  color-installed-locked "#A4A400000000";
  color-broken "";
  color-new "";
  UseStatusColors "true";
  CleanCache "false";
  AutoCleanCache "true";
  delHistory "-1";
  useProxy "0";
  httpProxy "";
  httpProxyPort "3128";
  ftpProxy "";
  ftpProxyPort "3128";
  noProxy "";
  DefaultDistro "maverick";
};

The bit with DefaultDistro "maverick"; was causing this issue for me.
For a quick one line solution you can run the following command:

release=`lsb_release -a 2>1| grep Codename| awk '{print $2}'`;for file in /root/.synaptic/synaptic.conf $HOME/.synaptic/synaptic.conf ; do sudo sed -i "s/DefaultDistro \".*;/DefaultDistro \"$release\";/g" $file; done;

[Jan Kronborg (magic75)]

I have tried both solutions suggested and I still get this error.
synaptic.conf did not even have a DefaultDistro entry, but adding a DefaultDistro "oneiric" did not help
Also tried creating /etc/apt/apt.conf with a APT::Default-Release entry, and that did not help either.

Where does synaptic/apt read this from???

[Mike Judkins (crazy-mike79)]

I replaced the natty with oneiric logged out/in and synaptic works fine now...thanx

[ketsa (ketsa-0)]

Same problem here after a squeeze --> wheezy upgrade :

I get :
E: The value 'squeeze-backports' is invalid for APT::Default-Release as such a release is not available in the sources
E: _cache->open() failed, please report.
When trying to open synaptic, it then closes.

I have no apt.conf, no /root/.synaptic folder and here is my /etc/apt/sources.list :

deb http://mirror.switch.ch/ftp/mirror/debian/ wheezy main contrib non-free
deb-src http://mirror.switch.ch/ftp/mirror/debian/ wheezy main contrib non-free

[Robert Roth (evfool)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug #880003, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Feel free to continue to report any other bugs you may find.
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