Double check there are tons of threads here your vblicense number is entered correct in your config-inc.php file and you can verify your cookie settings in photopost by viewing the settings table settings 171-173 and make sure they are set the same as vb
. You can rerun install again and input the proper info if needed and are not familar with phpmyadmin.
Cookie settings recommended are this
cookie path /
cookie prefix bb
cookie domain .domain.com