I'm doing a remote upgrade from 18.04 LTS to 20.4 LTS over ssh, trying to follow this recipe:  However, it seems the upgrade stopped while cleaning up the packages -- it detached from screen and never got to the &quot;System upgrade complete&quot; message. Running sudo do-release-upgrade -d again says &quot;There is no development version of an LTS available&quot;. Since this is remote, I'm afraid to reboot or do the wrong thing. How can I check/resume/fix the upgrade? Here's the last part of the /var/log/dist-upgrade/.../main.log: 2020-09-26 10:20:41,799 ERROR not handled exception: Traceback (most recent call last):    File &quot;/tmp/ubuntu-release-upgrader-soxxvnbe/DistUpgrade/DistUpgradeCache.py&quot;,  line 997, in tryMarkObsoleteForRemoval     self.restore_snapshot()    File &quot;/tmp/ubuntu-release-upgrader-soxxvnbe/DistUpgrade/DistUpgradeCache.py&quot;,  line 370, in restore_snapshot     pkg.mark_delete()    File &quot;/usr/lib/python3/dist-packages/apt/package.py&quot;, line 1509, in mark_delete  apt_pkg.Error: E:Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.   During handling of the above exception, another exception occurred:   Traceback (most recent call last):    File &quot;/tmp/ubuntu-release-upgrader-soxxvnbe/focal&quot;, line 8, in &lt;module&gt;     sys.exit(main())    File &quot;/tmp/ubuntu-release-upgrader-soxxvnbe/DistUpgrade/DistUpgradeMain.py&quot;, line 238, in main     if app.run():    File &quot;/tmp/ubuntu-release-upgrader-soxxvnbe/DistUpgrade/DistUpgradeController.py&quot;, line 2081, in run     return self.fullUpgrade()    File &quot;/tmp/ubuntu-release-upgrader-soxxvnbe/DistUpgrade/DistUpgradeController.py&quot;, line 2058, in fullUpgrade     self.doPostUpgrade()    File &quot;/tmp/ubuntu-release-upgrader-soxxvnbe/DistUpgrade/DistUpgradeController.py&quot;, line 1484, in doPostUpgrade     if not self.cache.tryMarkObsoleteForRemoval(pkgname, remove_candidates, self.forced_obsoletes, self.foreign_pkgs):    File &quot;/tmp/ubuntu-release-upgrader-soxxvnbe/DistUpgrade/DistUpgradeCache.py&quot;, line 243, in wrapper     res = f(*args, **kwargs)    File &quot;/tmp/ubuntu-release-upgrader-soxxvnbe/DistUpgrade/DistUpgradeCache.py&quot;, line 1001, in tryMarkObsoleteForRemoval     self.restore_snapshot()    File &quot;/tmp/ubuntu-release-upgrader-soxxvnbe/DistUpgrade/DistUpgradeCache.py&quot;, line 370, in restore_snapshot     pkg.mark_delete()    File &quot;/usr/lib/python3/dist-packages/apt/package.py&quot;, line 1509, in mark_delete  apt_pkg.Error: E:Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.
2011
I am not sure what caused this error, but here is what the whole error says, and also this is sitting as a notification, and preventing me from updating any software using Update Manager - Please provide some assistance or tell me how to figure out what to do to fix it.  Could not calculate the upgrade  An unresolvable problem occurred while calculating the upgrade.  Please report this bug against the 'update-manager' package and include the following error message: 'E:Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.'
111667
I am using Ubuntu 12.04 right now. If I use the command sudo apt-get dist-upgrade will that upgrade my Ubuntu to 12.10? Does that mean I won't be using the LTS version after that? I don't want to use Ubuntu 12.10 because I've already tried it and it's very heavy for my netbook.
44583
I just did a do-release-upgrade going from Ubuntu 16.04 to 17.04. However, now when I login via SSH I have the following message   Welcome to Ubuntu 17.04 (GNU/Linux 4.10.0-20-generic x86_64)   * Documentation:  https://help.ubuntu.com  * Management:     https://landscape.canonical.com  * Support:        https://ubuntu.com/advantage  Ubuntu 12.04 LTS end-of-life was April 28, 2017 -- Upgrade your Precise systems!  $ sudo do-release-upgrade -m server  0 packages can be updated. 0 updates are security updates.   My question is, how can I remove the   Ubuntu 12.04 LTS end-of-life was April 28, 2017 -- Upgrade your Precise systems!  $ sudo do-release-upgrade -m server   it wasn't there prior the release-upgrade  I checked and I am on Zesty  lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description:    Ubuntu 17.04 Release:    17.04 Codename:   zesty   My question is not, how can I remove this message, this I found. My question is more, is there a reason why this appears after a release-upgrade? Is this message something generic not taking into consideration the current version of Ubuntu? Or maybe my system is not updated properly?
50553
I use Ubuntu Studio 16.04 LTS, 64 bit, into 3 desktop PC (Intel i5 and i7) and 4 laptops (Intel Pentium). All with 8 GB of RAM.  Since about a week ago, I've been getting the following message each time I try to update/upgrade the system:  https://download.01.org/gfx/ubuntu/16.04/main xenial InRelease" has no Public Key. It isn't safe to use this kind of repository.   I tried to remove that repository (which I don't remember adding) with the terminal command:  sudo add-apt-repository -r &lt;repository to  remove&gt;   But, even though the system seems to perform that action, the repository is used next time I type:  sudo apt-get update   This repository isn't visible in Synaptic Software Manager and/or Ubuntu Software Center.  How can I fix it?
24538
So, today is July 21st and . gives me an option to download 16.04.1 LTS. However, attempting to upgrade gets me this message -  $ sudo do-release-upgrade Checking for a new Ubuntu release No new release found   What is wrong? Does it matter that I am running apt-get update behind apt-cacher-ng?  Note: Commenting out the files in apt.conf.d that used apt-cacher-ng did not make a difference.  Edit: Explanation for possible duplicates:  deals with upgrade from 12.04LTS to 14.04LTS. My question is specific to 14.04 LTS to 16.04.1 LTS upgrade. Old answers, while good for archival purposes are less relevant in a fast changing package like ubuntu. Moreover none of the answers answer what is wrong. The link  pointed out is mentioned in one of the comments. This Q &amp; A is more helpful for people upgrading today than the work around mentioned in "".
20435
I have  about how to upgrade ghostscript to a version that is available on 15.04 but not on 14.04LTS (which I have). On this site there are numerous almost identical question regarding different packages, a few examples include:         So I thought it would be very useful in general to know: is there  a general, automated way to upgrade a package, including all its dependencies, to a version that is newer than Ubuntu's repos? Is this more easily done if the newer version exists in more recent Ubuntu releases?
97036
I was under the impression that upgrading to Ubuntu 14.04 was supported from all version between and including the previous LTS release (12.04). Why is it then, that update-manager (with and without -d option) will only offer to upgrade to version 13.10 from my Ubuntu 12.10 system? Even that only works when I change the updater settings from "For long-term support versions" to "For any new version."  Is it only possible to upgrade to 14.04 via 13.10?
102164
I can't say what steps brought me into this:  → sudo apt-get upgrade  Reading package lists... Done Building dependency tree        Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. 1 not fully installed or removed. After this operation, 0 B of additional disk space will be used. Do you want to continue [Y/n]? y dpkg: error processing libtiff4 (--configure):  libtiff4:i386 3.9.5-1ubuntu1.1 cannot be configured because libtiff4:k386 is in a different version (3.9.5-1ubuntu1) Errors were encountered while processing:  libtiff4 E: Sub-process /usr/bin/dpkg returned an error code (1)   The following commands all end up in the same error:  sudo apt-get install -f sudo dpkg --configure -a sudo apt-get --fix-broken install sudo apt-get --fix-missing install sudo apt-get clean sudo apt-get autoclean sudo apt-get autoremove   How to solve these kind of problems? And what did I do wrong?  UPDATE I managed to get apt working again by downgrading to previous version (3.9.5-1ubuntu1). However, next upgrade led to the same problem. But there is more info now:  (Reading database ...  dpkg: warning: files list file for package `libtiff4:k386' missing, assuming package has no files currently installed. (Reading database ... 281166 files and directories currently installed.) Preparing to replace libtiff4 3.9.5-1ubuntu1 (using .../libtiff4_3.9.5-1ubuntu1.1_i386.deb) ... Unpacking replacement libtiff4 ... dpkg: error processing libtiff4 (--configure):  libtiff4:i386 3.9.5-1ubuntu1.1 cannot be configured because libtiff4:k386 is in a different version (3.9.5-1ubuntu1) No apport report written because MaxReports is reached already                                                               Errors were encountered while processing:  libtiff4   So the real problem seems to be the missing libtiff4:k386 package. And k386 seems like a stupid typo somewhere.  I tracked down the file that introduces the typo:  **/var/lib/dpkg/status**  Package: libtiff4 Status: install ok half-configured Multi-Arch: same Priority: optional Section: libs Installed-Size: 528 Maintainer: Ubuntu Developers &lt;ubuntu-devel-discuss@lists.ubuntu.com&gt; Architecture: k386 Source: tiff Version: 3.9.5-1ubuntu1 Config-Version: 3.9.5-1ubuntu1 Depends: libc6 (&gt;= 2.11), libjpeg62 (&gt;= 6b1), zlib1g (&gt;= 1:1.1.4) Pre-Depends: multiarch-support Description: Tag Image File Format (TIFF) library  libtiff is a library providing support for the Tag Image File Format  (TIFF), a widely used format for storing image data.  This package  includes the shared library. Homepage: http://libtiff.maptools.org Original-Maintainer: Jay Berkenbilt &lt;qjb@debian.org&gt;   Fixing the typo solves the problem.
100260
I typed  sudo apt-get upgrade   And I got this  $ sudo apt-get upgrade Reading package lists... Done Building dependency tree        Reading state information... Done Calculating upgrade... Done The following packages will be upgraded:   bind9-host dnsutils google-chrome-stable libbind9-161 libdns-export1104   libdns1104 libirs161 libisc-export1100 libisc1100 libisccc161 libisccfg163   liblwres161 python3-distupgrade ubuntu-release-upgrader-core   ubuntu-release-upgrader-gtk 15 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. Need to get 0 B/61.1 MB of archives. After this operation, 1,769 kB of additional disk space will be used. Do you want to continue? [Y/n]  dpkg: unrecoverable fatal error, aborting:  unknown system group 'smmsp' in statoverride file; the system group got removed before the override, which is most probably a packaging bug, to recover you can remove the override manually with dpkg-statoverride E: Sub-process /usr/bin/dpkg returned an error code (2)   Can any one throw any light on this?
24529
I've upgraded my LTS version of Ubuntu to Ubuntu 17.04 and from the day I've upgraded I've been struggling to get this thing stable. Sometimes my Wifi adapter doesn't work properly and sometimes I can't even copy things properly.  So I want to revert back to Ubuntu 16.04 LTS.  Is there any way to get this done?
87280
I am running the upgrade(12.10 to 13.04) through terminal and it keeps getting stuck at this:  Failed to lock /var/cache/apt/archives/lock   What do I do? I have root access. I have no idea what else to try other than a clean install.  Checking package manager Reading package lists... Done     Building dependency tree           Reading state information... Done Building data structures... Done   Calculating the changes Calculating the changes  Do you want to start the upgrade?   3 packages are going to be removed. 155 new packages are going to be  installed. 1204 packages are going to be upgraded.   You have to download a total of 595 M. This download will take about  1 hour 15 minutes with a 1Mbit DSL connection and about 23 hours with  a 56k modem.   Fetching and installing the upgrade can take several hours. Once the  download has finished, the process cannot be canceled.    Continue [yN]  Details [d]y  Fetching  Could not download the upgrades   The upgrade has aborted. Please check your Internet connection or  installation media and try again. All files downloaded so far have  been kept.   Failed to lock /var/cache/apt/archives/lock    Restoring original system state  Aborting Reading package lists... Done     Building dependency tree           Reading state information... Done Building data structures... Done  root@chaitanya-XPS-Ubuntu:~#
45893
I followed these instructions to upgrade from 19.10 to 20.04:    I understand the  was 2 days ago. However, when I run the following as instructed:  Press Alt+F2 and type update-manager -c -d into the command box.    The popup shows:    I want the final release, not the development release.  I am following the official ubuntu instructions.  What am I doing wrong?  These are my update settings, which should just be LTS:
61688
I have Ubuntu 10 server and want to update a package to newer version (update rrdtool from 1.3.8 to current 1.4.5). What should I do? Download and build sources or get package from newer distribution? And how to do that?
116376
I wanted to reinstall the APT Tool, so I uninstalled it, and then I realized that it probably would've been better if I just deleted the /etc/apt directory. Is there any way that I can fix my screw-up?  My Ubuntu version is 18.04.2 LTS and the output of ls /etc/apt was   root@user-OptiPlex-755:~# ls /etc/apt  ls: cannot access '/etc/apt': No such file or directory   UPDATE: I have re-installed apt, however, this is my output:  root@user-OptiPlex-755:~# sudo apt install --reinstall apt-utils ubuntu-minimal ubuntu-release-upgrader-gtk ubuntu-desktop update-manager update-notifier update-notifier-common Reading package lists... Done Building dependency tree        Reading state information... Done Package update-manager is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source However the following packages replace it: ubuntu-release-upgrader-core update-manager-core  Package update-notifier-common is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  Package update-notifier is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source However the following packages replace it: update-notifier-common  Package apt-utils is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source However the following packages replace it: apt  Package ubuntu-release-upgrader-gtk is not available, but is referred to by another package. This may mean that the package is missing, has been obsoleted, or is only available from another source  E: Package 'apt-utils' has no installation candidate E: Unable to locate package ubuntu-minimal E: Package 'ubuntu-release-upgrader-gtk' has no installation candidate E: Unable to locate package ubuntu-desktop E: Package 'update-manager' has no installation candidate E: Package 'update-notifier' has no installation candidate E: Package 'update-notifier-common' has no installation candidate`
120314
and I update/upgrade by   apt update  then  apt upgrade   what has replaced:  apt-get autoremove ?   As near as I can tell there is no  apt autoremove   command?
103972
I upgraded to Ubuntu 14.04 but it shows a red symbol on the top and gives error message in function update  E:unknown error:&lt;type exceptions.type error&gt; upgrade manager or any other file is not present
115909
I upgraded from 18.04 to 19.10 some months ago and now I want to upgrade to 20.04. But update-manager -c doesn't show the new Ubuntu release 20.04.  Isn't the upgrade ready yet? Is it possible to upgrade to 20.04 from 19.10 now?