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