What does Unknown media type in type 'all/all' mean? [duplicate]

Solution 1:

it is a bug, see https://bugs.launchpad.net/ubuntu/+source/shared-mime-info/+bug/289592

try

sudo rm /usr/share/mime/packages/kde.xml 
sudo update-mime-database /usr/share/mime

Solution 2:

Not sure what the error means but I'll share with you what worked for me.

Basically just delete all the erroneous mime-types in the kde.xml file.

After that run:

sudo update-mime-database /usr/share/mime

The first two should look something like;

<mime-type type="all/all">
  <comment>all files and folders</comment>
  </mime-type>
  <mime-type type="all/allfiles">
  <comment>all files</comment>
</mime-type>

Do likewise with the rest, then logout/login as needed.

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