No data after update 1.51 to 1.6

Hi all,

i updated manually to 1.6. No errors. Then the update from the DB . Succesfully changed.
So i started piwik…but no graphs and no Data. The website is correctly and all settings are there . But if i trigg something nothing happens.
What could i do wrong or change that it will work again??

thx a lot for help