API returned an error: SQLSTATE[42S22]: Column not found: 1054 Unknown column 'log_link_visit_action.idaction_content_name' in 'where clause' at Pdo.php:234
This error shows at the top of index.php?module=MultiSites&action=index&idSite=2&period=day&date=today
Thanks for the report, please activate the plugin Contents to solve the issue.
There is no plugin called Contents on my system, and a search for Contents under 'Extend Piwik by installing a new plugin' shows no results.
I had already upgraded to Piwik 2.7.0 when submitting this bug, this is when the issue began (as per the title).
Under Settings -> Plugins list I have Actions, Annotations, Custom Variables, Dashboard, in alphabetical order. There is no Contents plugin.
so please re-upload 2.7.0 as there should be a folder plugins/Contents/