I received an error.
WP Super Cache is not properly configured to work with Simple:Press. Please visit your WP Super Cache Settings Page and in the Accepted Filenames & Rejected URIs Section for the pages not to be cached input field, add the following string:
Then, please clear your WP Super Cache to remove any cached Simple:Press pages.
I added /forum/ where do I clear WP Super Cache? I cannot find a "Clear WP Super Cache" anywhere.