Completely start afresh after premium install

Hello,

I had a premium version of the Mailpoet plugin installed on a website and I would like to start a fresh, by installing the free version etc.

I tried uninstalling the previous version, deleted the plugin’s tables and the entries in the WordPress options table, yet upon re-installing the free version I am getting a lot of database related errors and the plugin is not retrieving the user list properly etc.

Can you please advise what I should delete to ensure the new installation is a fresh install?

Thank you.

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