Please remove the .htaccess and .htpasswd files from your site's administrator folder. Then go back to Admin Tools and re-enable the Administrator Password Protection.
If you still get the 404 error after re-enabling the Administrator Password Protection you need to contact your host and tell them this:
Your server is configured to use custom HTTP error documents. These documents are either inaccessible or simply do not exist. This causes HTTP Basic Authentication for my site's administrator folder to fail since the custom HTTP 401 error document does not exist and results in a 404 error. Please disable custom error documents from Apache or point me out to the instructions which will let me do that.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
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