I recently installed Piwik 0.9 (fresh install) which went fine and without any problems at all.
But when I try to login as admin, I just got the error message that the “security key is invalid” and that I should check if cookies are enabled in my browser.
I don’t have this problem with Piwik installations, just with this one. Cookies are enabled, Cache and old Cookies are cleared.
Any ideas? style_emoticons/<#EMO_DIR#>/sad.gif