I get this error almost daily when I try to view Visitors/E-commerce logs. Sometimes instead of the error below, I get No Data Received error in the browser. The error goes away after upgrading piwik to the new version or reinstalling piwik by deleting the config.ini.php file. Is this a cache issue? My server is using Redis cache. I don’t see any errors in the logs. Any help is appreciated.
Oops… there was a problem during the request. Maybe the server had a temporary issue, or maybe you requested a report with too much data. Please try again. If this error occurs repeatedly please contact your Piwik administrator for assistance.