Unable to configure Coursepress Pro

I had the free version of Coursepress and then upgraded to the paid version(Coursepress Pro). After installing the plugin when I click on configure, I get this error
---403 Forbidden
Permission denied. Our sentries tell us that you should not be here.
Website owner? If you think you have reached this message in error, please contact support.
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My WP plugins dashboard prompts me to back-up and upgrade from Coursepress1 to Coursepress2, but when I try to do it I repetedly get a Unsuccessful upgrade message