[Plugin: W3 Total Cache] Problems with w3 total cache

On trying to activate the plugin i get a fatal error:

/srv/www/vhosts/default/htdocs/company_new/wp-content/w3tc/dbcache could not be created, please run following command:
chmod 777 /srv/www/vhosts/default/htdocs/company_new/wp-content/w3tc
then.

But wp-content does have permission to write. If i try to create a folder called w3tc manually and then reactivate the plugin, the folder gets deleted and the errormessage appears again.

Any hints or tricks?!