I need help with .htaccess so that requests for: http://www.mydomain.com/directory123/name-of-post.html is redirected to: http://www.mydomain.com/name-of-post.html EXCEPT requests for the WP backend are not redirected: http://www.mydomain.com/directory123/wp-login etc are unchanged. Paypal payment. I prefer to pay after success, please check my iTrader. Most trustworthy DPer gets the job.
Go to WP Admin -> Settings and change the Wordpress URL to http://www.mydomain.com/directory123/ and not just mydomain.com add the directory. It's not a .htaccess problem.