This page should only be displayed as long as there wasn't any data tracked at all for the current selected website. As soon as the first data was tracked, that page automatically disappears.

@sgiehl , thanks for your answer. The problem is that i've data tracked for the selected website.
Lets me explain : for the range last90 i've that page on the index.php. BUT i've data if in database, i've data if i use the API and i've my dashboard if i use the plugin dashboard directly.

are you using javascript tracking or the log importer?

javascript tracking

Had a small look at the code. The query used to check if a site has no data is here:
https://github.com/piwik/piwik/blob/master/core/Tracker/Model.php#L420
I can't see a reason why it should return nothing if there is data in the log_visit table.

Interresting. When I execute the sql request on my db, I've empty row. But I've still data tracked on the "all websites dashboard" for a range of last90. The log_visit table is archived, isn't it ?

Have you enabled the option to remove old log data? By default the data won't be removed. But if so, it might be possible that there are no entries in the log tables for website that don't have recent data tracked. Guess we would need to extend the check for already archived data

Hum, no, the option to remove old log data is disabled.. I don't know the code, but maybe the core:update do a archive of current log in order to speedup or something ?

When you request the API to fetch data, can you make sure you fetch the correct idSite?

@candaj please re-open if you still experience this issue with Piwik 2.16.0