Comment 22 for bug 1592669

Hi,

Sorry, this is on us: We've had a fix for this in review for a while, but haven't been able to push it to completion (it's a fairly big change to how the packaging works).

I'm not familiar with the error you're getting with the enable command (doesn't happen on my box. I get the warning but not the error), but a second workaround you can try until we can get this fix into the package is:
* Edit /var/lib/dpkg/info/mysql-server-5.7.postinst and put a simple "exit 0" at the top after #!/bin/bash
* Run apt-get -f install

This will skip the entire postinst script, which basically has two purposes:
a) On a fresh install, setup the default database, root access, etc.
b) On an upgrade, start the new server version, run mysql_upgrade, then restart the server

a) Shouldn't apply in your case, but it's important you do b)

Hopefully this helps