desktop environments - Unity shows wrong distribution name - Ask Ubuntu

recently had installed pantheon (elementary os desktop environment). didn't it, uninstalled it, elementary os desktop still appear in title bar. , in shutdown button menu, ubuntu help replaced elementary os help.

i want says ubuntu desktop , ubuntu help. how fix it?

the output of lsb_release -a is:

no lsb modules available. distributor id: elementary description:    elementary os 0.4 loki release:        0.4 codename:       loki 

for installation, use:

sudo add-apt-repository ppa:elementary-os/daily  sudo add-apt-repository ppa:elementary-os/os-patches sudo add-apt-repository ppa:elementary-os/testing  sudo add-apt-repository ppa:mpstark/elementary-tweaks-daily  sudo apt-get update sudo apt-get dist-upgrade sudo apt-get install elementary-theme elementary-icon-theme elementary-default-settings elementary-desktop 

for uninstallation, remove each repository manually, sudo apt-get autoremove. , rest synaptic package manager.

the ppas used install elementary not provided elementary specific packages, patched many standard ubuntu packages , apt-get dist-upgrade command installed , mixed system. means of core packages not ubuntu repository, elementary ppas.

for example, ppa https://launchpad.net/~elementary-os/+archive/ubuntu/os-patches provides many packages available in ubuntu repository. since ppa provides package higher version (and patched of course), preferred apt , installed system while did dist-upgrade command.

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for specific problem, identified package responsible showing distribution name on top-left corner of unity panel. called base-files. tested elementary ppa installing , not surprisingly got elementary marks :d.

but solve this, can't remove it, because essential package , ubuntu needs it. need re-installing ubuntu repository. use command so.

sudo apt-get --reinstall install base-files/xenial-updates 

this command install package ubuntu's xenial-updates archive. after logout , login, you'll see changes reverted back.

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to remove elementary effect system, should go ubuntu versions packages. so, use ppa-purge (and not apt-add-repository --remove command, remove repository entry). example,

sudo ppa-purge ppa:elementary-os/daily  sudo ppa-purge ppa:elementary-os/os-patches sudo ppa-purge ppa:elementary-os/testing  sudo ppa-purge ppa:mpstark/elementary-tweaks-daily 

ppa-purge remove packages these ppas , install ones ubuntu archives.

note: if removed elementary ppa entries (by deleting lines sources.list files) add them again , use ppa-purge.