Wordpress not allow installing wordpress into subdirectory name with blog. Here are some step to remove this restrictions. WordPress hook directory : subdirectory_reserved_names Wp-admin/ms-edit.php line no:154 //$subdirectory_reserved_names = apply_filters( 'subdirectory_reserved_names', array( 'page', 'comments', 'blog', 'files', 'feed' ) ); $subdirectory_reserved_names = apply_filters( 'subdirectory_reserved_names', array( 'page', 'comments', 'files', 'feed' ) ); Wp-includes/ms-functions.php line no:516 //$subdirectory_reserved_names = apply_filters( 'subdirectory_reserved_names', array( 'page', 'comments', 'blog', 'files', 'feed' ) ); $subdirectory_reserved_names = apply_filters( 'subdirectory_reserved_names', array( 'page', 'comments', 'files', 'feed' ) ); OR Wp-includes/ms-functions.php on line 559 if (! is_subdomain_install() ) //$illegal_names = array_merge($illegal_names, apply_filters( 'subdirectory_reserved_names', array( 'page', 'comments', 'blog', 'files', 'feed' ) ) ); $illegal_names = array_merge($illegal_names, apply_filters( 'subdirectory_reserved_names', array( 'page', 'comments', 'files', 'feed' ) ) );   Wp-includes/ms-settings.php Line no: 73 //$reserved_blognames = array( 'page', 'comments', 'blog', 'wp-admin', 'wp-includes', 'wp-content', 'files', 'feed' ); $reserved_blognames =…