Clicking on Api - Link shows empty page

Hello,

I updated from Piwik 0.2.26 to 0.2.28 yesterday. Since that time, clicking on the Api-Link in my Dashboard shows me an empty page. Even the source of the page http://-deleted-by-me-/piwik/index.php?module=API&action=listAllAPI&idSite=1&period=day&date=yesterday is totally empty.

Amy ideas what could be the problem?

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Second problem since 0.2.28: The table at actions -> pages shows no further entries when I click on one of the labels/categories that have a “+” in front of them. For example I have the label/category restaurants that showed several entries every day until the update to 0.2.28. Now it only says “No data in this category.”

If you click on “Include all population”, does it show all data?