This is the first result on a google search for the matter, so I just wanted to add my solution.

The command that was attempted to be run by the "akonadictl start" command was /usr/sbin/mysqld

Looking at file:

Code: Select all

/etc/apparmor.d/usr.sbin.mysqld

There is no line to allow permission into a users home.

Looking at:

Code: Select all

/etc/apparmor.d/usr.sbin.mysqld-akonadi

We see this line, among others:

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@{HOME}/.local/share/akonadi/** rwk,

So I ran:

Code: Select all

kcmshell4 kcm_akonadi

And on the second tab I changed the command from /usr/sbin/mysqld to /usr/sbin/mysqld-akonadi

All solved.

You changed the location of your HOME folder, including symlinking, it's Apparmor.
I had the same problem.

Edit /etc/apparmor.d/tunable/home and add your new home

Example
@{HOMEDIRS}=/home/
to
@{HOMEDIRS}=/home/ /somewhere/home/

then
sudo /etc/init.d/apparmor restart

All solved