And when running "sudo appstreamcli refresh --force --verbose" the output is as follows:
** (appstreamcli:2227): DEBUG: Refreshing AppStream cache
** (appstreamcli:2227): DEBUG: Reading: /usr/share/app-info/xmls/org.freedesktop.fwupd.xml
** (appstreamcli:2227): DEBUG: Reading: /var/lib/app-info/yaml/gb.archive.ubuntu.com_ubuntu_dists_xenial_universe_dep11_Components-amd64.yml.gz
** (appstreamcli:2227): DEBUG: Reading: /var/lib/app-info/yaml/gb.archive.ubuntu.com_ubuntu_dists_xenial-updates_main_dep11_Components-amd64.yml.gz
** (appstreamcli:2227): DEBUG: Reading: /var/lib/app-info/yaml/gb.archive.ubuntu.com_ubuntu_dists_xenial_multiverse_dep11_Components-amd64.yml.gz
** (appstreamcli:2227): DEBUG: Reading: /var/lib/app-info/yaml/gb.archive.ubuntu.com_ubuntu_dists_xenial_main_dep11_Components-amd64.yml.gz
** (appstreamcli:2227): DEBUG: Reading: /var/lib/app-info/yaml/gb.archive.ubuntu.com_ubuntu_dists_xenial_restricted_dep11_Components-amd64.yml.gz
** (appstreamcli:2227): DEBUG: Reading: /var/lib/app-info/yaml/gb.archive.ubuntu.com_ubuntu_dists_xenial-updates_restricted_dep11_Components-amd64.yml.gz
** (appstreamcli:2227): DEBUG: Reading: /var/lib/app-info/yaml/gb.archive.ubuntu.com_ubuntu_dists_xenial-updates_universe_dep11_Components-amd64.yml.gz
** (appstreamcli:2227): DEBUG: Reading: /var/lib/app-info/yaml/gb.archive.ubuntu.com_ubuntu_dists_xenial-updates_multiverse_dep11_Components-amd64.yml.gz
** (appstreamcli:2227): DEBUG: Reading: /var/lib/app-info/yaml/security.ubuntu.com_ubuntu_dists_xenial-security_main_dep11_Components-amd64.yml.gz
** (appstreamcli:2227): DEBUG: Reading: /var/lib/app-info/yaml/security.ubuntu.com_ubuntu_dists_xenial-security_restricted_dep11_Components-amd64.yml.gz
** (appstreamcli:2227): DEBUG: Reading: /var/lib/app-info/yaml/security.ubuntu.com_ubuntu_dists_xenial-security_universe_dep11_Components-amd64.yml.gz
** (appstreamcli:2227): DEBUG: Reading: /var/lib/app-info/yaml/security.ubuntu.com_ubuntu_dists_xenial-security_multiverse_dep11_Components-amd64.yml.gz
** (appstreamcli:2227): DEBUG: Reading: /var/cache/app-info/xmls/fwupd.xml
** (appstreamcli:2227): DEBUG: Detected colliding ids: plan.desktop was already added with the same priority.
** (appstreamcli:2227): DEBUG: Detected colliding ids: flcheckers.desktop was already added with the same priority.
** (appstreamcli:2227): DEBUG: Detected colliding ids: flblocks.desktop was already added with the same priority.
** (appstreamcli:2227): DEBUG: Detected colliding ids: flsudoku.desktop was already added with the same priority.
** (appstreamcli:2227): DEBUG: zathura-pdf-poppler.desktop extends zathura.desktop, but zathura.desktop was not found.
** (appstreamcli:2227): DEBUG: WARNING: Skipped component 'com.steelseries.rival-legacy.firmware': The component is invalid.
** (appstreamcli:2227): DEBUG: Removing old rebuild-dir from previous database rebuild.
AppStream cache update completed, but some metadata was ignored due to errors.
I have found this to be present on all Ubuntu 16.04 flavours which I have tried, I have also been informed that this is likely to be a server-side issue.
I have found that when there are new packages available which my machine doesn't know about yet, if I run "sudo apt-get update" this is the output:
Get:1 http:// gb.archive. ubuntu. com/ubuntu xenial InRelease [247 kB] security. ubuntu. com/ubuntu xenial-security InRelease gb.archive. ubuntu. com/ubuntu xenial-updates InRelease [82.2 kB] security. ubuntu. com/ubuntu xenial- security/ main i386 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial-backports InRelease [82.2 kB] security. ubuntu. com/ubuntu xenial- security/ restricted i386 Packages [28 B] security. ubuntu. com/ubuntu xenial- security/ universe i386 Packages [28 B] security. ubuntu. com/ubuntu xenial- security/ multiverse amd64 Packages [28 B] security. ubuntu. com/ubuntu xenial- security/ multiverse i386 Packages [28 B] security. ubuntu. com/ubuntu xenial- security/ multiverse Translation-en [28 B] gb.archive. ubuntu. com/ubuntu xenial/main amd64 Packages [1,201 kB] gb.archive. ubuntu. com/ubuntu xenial/main i386 Packages [1,196 kB] gb.archive. ubuntu. com/ubuntu xenial/main Translation-en_GB [426 kB] gb.archive. ubuntu. com/ubuntu xenial/main Translation-en [568 kB] gb.archive. ubuntu. com/ubuntu xenial/main amd64 DEP-11 Metadata [733 kB] gb.archive. ubuntu. com/ubuntu xenial/main DEP-11 64x64 Icons [409 kB] gb.archive. ubuntu. com/ubuntu xenial/restricted amd64 Packages [8,344 B] gb.archive. ubuntu. com/ubuntu xenial/restricted i386 Packages [8,684 B] gb.archive. ubuntu. com/ubuntu xenial/restricted Translation-en_GB [2,556 B] gb.archive. ubuntu. com/ubuntu xenial/restricted Translation-en [2,908 B] gb.archive. ubuntu. com/ubuntu xenial/restricted amd64 DEP-11 Metadata [186 B] gb.archive. ubuntu. com/ubuntu xenial/universe amd64 Packages [7,532 kB] gb.archive. ubuntu. com/ubuntu xenial/universe i386 Packages [7,512 kB] gb.archive. ubuntu. com/ubuntu xenial/universe Translation-en_GB [3,040 kB] gb.archive. ubuntu. com/ubuntu xenial/universe Translation-en [4,354 kB] gb.archive. ubuntu. com/ubuntu xenial/universe amd64 DEP-11 Metadata [3,410 kB] gb.archive. ubuntu. com/ubuntu xenial/universe DEP-11 64x64 Icons [7,448 kB] gb.archive. ubuntu. com/ubuntu xenial/multiverse amd64 Packages [144 kB] gb.archive. ubuntu. com/ubuntu xenial/multiverse i386 Packages [140 kB] gb.archive. ubuntu. com/ubuntu xenial/multiverse Translation-en_GB [88.1 kB] gb.archive. ubuntu. com/ubuntu xenial/multiverse Translation-en [106 kB] gb.archive. ubuntu. com/ubuntu xenial/multiverse amd64 DEP-11 Metadata [63.8 kB] gb.archive. ubuntu. com/ubuntu xenial/multiverse DEP-11 64x64 Icons [230 kB] gb.archive. ubuntu. com/ubuntu xenial-updates/main amd64 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial-updates/main i386 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial-updates/main Translation-en [28 B] gb.archive. ubuntu. com/ubuntu xenial- updates/ restricted amd64 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- updates/ restricted i386 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- updates/ restricted Translation-en [28 B] gb.archive. ubuntu. com/ubuntu xenial- updates/ universe amd64 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- updates/ universe i386 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- updates/ universe Translation-en [28 B] gb.archive. ubuntu. com/ubuntu xenial- updates/ multiverse amd64 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- updates/ multiverse i386 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- updates/ multiverse Translation-en [28 B] gb.archive. ubuntu. com/ubuntu xenial- backports/ main amd64 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- backports/ main i386 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- backports/ main Translation-en [28 B] gb.archive. ubuntu. com/ubuntu xenial- backports/ restricted amd64 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- backports/ restricted i386 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- backports/ restricted Translation-en [28 B] gb.archive. ubuntu. com/ubuntu xenial- backports/ universe amd64 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- backports/ universe i386 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- backports/ universe Translation-en [28 B] gb.archive. ubuntu. com/ubuntu xenial- backports/ multiverse amd64 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- backports/ multiverse i386 Packages [28 B] gb.archive. ubuntu. com/ubuntu xenial- backports/ multiverse Translation-en [28 B]
Hit:2 http://
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Fetched 39.0 MB in 7min 59s (81.3 kB/s)
AppStream cache update completed, but some metadata was ignored due to errors.
Reading package lists... Done
And when running "sudo appstreamcli refresh --force --verbose" the output is as follows:
** (appstreamcli: 2227): DEBUG: Refreshing AppStream cache 2227): DEBUG: Reading: /usr/share/ app-info/ xmls/org. freedesktop. fwupd.xml 2227): DEBUG: Reading: /var/lib/ app-info/ yaml/gb. archive. ubuntu. com_ubuntu_ dists_xenial_ universe_ dep11_Component s-amd64. yml.gz 2227): DEBUG: Reading: /var/lib/ app-info/ yaml/gb. archive. ubuntu. com_ubuntu_ dists_xenial- updates_ main_dep11_ Components- amd64.yml. gz 2227): DEBUG: Reading: /var/lib/ app-info/ yaml/gb. archive. ubuntu. com_ubuntu_ dists_xenial_ multiverse_ dep11_Component s-amd64. yml.gz 2227): DEBUG: Reading: /var/lib/ app-info/ yaml/gb. archive. ubuntu. com_ubuntu_ dists_xenial_ main_dep11_ Components- amd64.yml. gz 2227): DEBUG: Reading: /var/lib/ app-info/ yaml/gb. archive. ubuntu. com_ubuntu_ dists_xenial_ restricted_ dep11_Component s-amd64. yml.gz 2227): DEBUG: Reading: /var/lib/ app-info/ yaml/gb. archive. ubuntu. com_ubuntu_ dists_xenial- updates_ restricted_ dep11_Component s-amd64. yml.gz 2227): DEBUG: Reading: /var/lib/ app-info/ yaml/gb. archive. ubuntu. com_ubuntu_ dists_xenial- updates_ universe_ dep11_Component s-amd64. yml.gz 2227): DEBUG: Reading: /var/lib/ app-info/ yaml/gb. archive. ubuntu. com_ubuntu_ dists_xenial- updates_ multiverse_ dep11_Component s-amd64. yml.gz 2227): DEBUG: Reading: /var/lib/ app-info/ yaml/security. ubuntu. com_ubuntu_ dists_xenial- security_ main_dep11_ Components- amd64.yml. gz 2227): DEBUG: Reading: /var/lib/ app-info/ yaml/security. ubuntu. com_ubuntu_ dists_xenial- security_ restricted_ dep11_Component s-amd64. yml.gz 2227): DEBUG: Reading: /var/lib/ app-info/ yaml/security. ubuntu. com_ubuntu_ dists_xenial- security_ universe_ dep11_Component s-amd64. yml.gz 2227): DEBUG: Reading: /var/lib/ app-info/ yaml/security. ubuntu. com_ubuntu_ dists_xenial- security_ multiverse_ dep11_Component s-amd64. yml.gz 2227): DEBUG: Reading: /var/cache/ app-info/ xmls/fwupd. xml 2227): DEBUG: Detected colliding ids: plan.desktop was already added with the same priority. 2227): DEBUG: Detected colliding ids: flcheckers.desktop was already added with the same priority. 2227): DEBUG: Detected colliding ids: flblocks.desktop was already added with the same priority. 2227): DEBUG: Detected colliding ids: flsudoku.desktop was already added with the same priority. 2227): DEBUG: zathura- pdf-poppler. desktop extends zathura.desktop, but zathura.desktop was not found. 2227): DEBUG: WARNING: Skipped component 'com.steelserie s.rival- legacy. firmware' : The component is invalid. 2227): DEBUG: Removing old rebuild-dir from previous database rebuild.
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
** (appstreamcli:
AppStream cache update completed, but some metadata was ignored due to errors.
I have found this to be present on all Ubuntu 16.04 flavours which I have tried, I have also been informed that this is likely to be a server-side issue.