You are trying to login into your WordPress website. Being told by your own website that you’re “not authorized to view this page,” also known as a 403 error; the ultimate of obnoxious ironies. Unfortunately, this bug is all too common.
Often you’re looking at problems with Directory Indexes, associated with blogs hosted on Windows servers. You can resolve this error by simply adding “index.php” to the Directory Indexes, just by going to Control Panel > Web Options > Directory Indexes.