Fatal error: Class 'Piwik_Date' not found in [...]

Hi!

After successful installation on the web server I get this error message:

Fatal error: Class ‘Piwik_Date’ not found in /www/htdocs/w00a9f69/Bullireisend/Blog/piwik/core/Controller.php on line 57

Does anybody know how to handle it?

Thanks!
Martin

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