I am receiving the following message when trying to access my Magento admin back end and the website.
The requested URL /index.php/rsc_sales_admin_back_end/catalog_product/index/key/194c206c2f43d5a39feca0e9ca34ec5d/ was not found on this server.
Please advise if you have any thoughts or suggestions. Thank you.
can you please let me know if you have done any changes to Magento configuration or your server recently? Also do you have any problems for your Magento frontend?
As @Swissuplabscom said you should provide more information.
Maybe the backend URL was changed and that' why you can access.
You should check the right admin (custom) path into the database.