Can I use the free Wordpress.com blog with OptimizePress
I'm afraid you cannot use OptimizePress on any Wordpress.com blog or site. Wordpress.com is the hosted blog service from WordPress but they are not open source and have enough differences from the self hosted WordPress that we can not offer support for using wordpress.com
WordPress.com is a closed system and not open source like the self hosted version of WordPress from WordPress.org. This means that both WordPress.com/org versions are very different and do not have all the exact same features or all the same codes. While they are both "WordPress" we only support the self hosted version.
WordPress.com does not provide any access to the back end files of your site which makes it impossible for our team to do any advanced troubleshooting should the need arise. It is unfortunate, but due to these facts, and with how complex/advanced of a plugin OptimizePress is, we can not provide any support or troubleshooting if you choose to use WordPress.com for your web host.
You need to actually have your own web hosting and not use the Wordpress.com Wordpress service - as you will see on our sales page, you need to use the Wordpress.org script on your own hosting. The script itself is free but it must be on your own hosting.
The WordPress.com system only recently started allowing 3rd party plugins and themes to be installed (within the last couple years), however as their system is closed and not open source, we are not able to offer any guarantees or support for OptimizePress being used on WordPress.com
We recommend following the tutorials in the members area on how to setup your hosting and domain if you're not sure how to do this first - then follow in the install tutorials for setting up wordpress on your site.
We recommend SiteGround if you have not yet chosen a web host -