Blocking-Problem

Hi,

today I installed Piwik on my site. Ninja Firewall now is blocking some files, I think. I can use Piwik if I disable the Firewall and if I enable it, there are Errors displayed:

Please check that the web server has enough permission to write to these files/directories:
For example, on a GNU/Linux server if your Apache httpd user is , you can try to execute

and

“Debug: the original error was
session has already been started by session.auto-start or sess”

Is there a way to tell the firewall, that Piwik is no aggressor?

Regards
Daniel

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