再上传。打开wp-admin/includes/file.php文件，目前wordpress简体中文版最新为WordPress 4.9.4。删除492-599行如下代码：

if ( $is_active && 'php' === $extension ) {		$scrape_key = md5( rand() );		$transient = 'scrape_key_' . $scrape_key;		$scrape_nonce = strval( rand() );		set_transient( $transient, $scrape_nonce, 60 ); // It shouldn't take more than 60 seconds to make the two loopback requests.		$cookies = wp_unslash( $_COOKIE );		$scrape_params = array(			'wp_scrape_key' => $scrape_key,			'wp_scrape_nonce' => $scrape_nonce,		);		$headers = array(			'Cache-Control' => 'no-cache',		);		// Include Basic auth in loopback requests.		if ( isset( $_SERVER['PHP_AUTH_USER'] ) && isset( $_SERVER['PHP_AUTH_PW'] ) ) {			$headers['Authorization'] = 'Basic ' . base64_encode( wp_unslash( $_SERVER['PHP_AUTH_USER'] ) . ':' . wp_unslash( $_SERVER['PHP_AUTH_PW'] ) );		}		// Make sure PHP process doesn't die before loopback requests complete.		@set_time_limit( 300 );		// Time to wait for loopback requests to finish.		$timeout = 100;		$needle_start = "###### wp_scraping_result_start:$scrape_key ######";		$needle_end = "###### wp_scraping_result_end:$scrape_key ######";		// Attempt loopback request to editor to see if user just whitescreened themselves.		if ( $plugin ) {			$url = add_query_arg( compact( 'plugin', 'file' ), admin_url( 'plugin-editor.php' ) );		} elseif ( isset( $stylesheet ) ) {			$url = add_query_arg(				array(					'theme' => $stylesheet,					'file' => $file,				),				admin_url( 'theme-editor.php' )			);		} else {			$url = admin_url();		}		$url = add_query_arg( $scrape_params, $url );		$r = wp_remote_get( $url, compact( 'cookies', 'headers', 'timeout' ) );		$body = wp_remote_retrieve_body( $r );		$scrape_result_position = strpos( $body, $needle_start );		$loopback_request_failure = array(			'code' => 'loopback_request_failed',			'message' => __( 'Unable to communicate back with site to check for fatal errors, so the PHP change was reverted. You will need to upload your PHP file change by some other means, such as by using SFTP.' ),		);		$json_parse_failure = array(			'code' => 'json_parse_error',		);		$result = null;		if ( false === $scrape_result_position ) {			$result = $loopback_request_failure;		} else {			$error_output = substr( $body, $scrape_result_position + strlen( $needle_start ) );			$error_output = substr( $error_output, 0, strpos( $error_output, $needle_end ) );			$result = json_decode( trim( $error_output ), true );			if ( empty( $result ) ) {				$result = $json_parse_failure;			}		}		// Try making request to homepage as well to see if visitors have been whitescreened.		if ( true === $result ) {			$url = home_url( '/' );			$url = add_query_arg( $scrape_params, $url );			$r = wp_remote_get( $url, compact( 'cookies', 'headers', 'timeout' ) );			$body = wp_remote_retrieve_body( $r );			$scrape_result_position = strpos( $body, $needle_start );			if ( false === $scrape_result_position ) {				$result = $loopback_request_failure;			} else {				$error_output = substr( $body, $scrape_result_position + strlen( $needle_start ) );				$error_output = substr( $error_output, 0, strpos( $error_output, $needle_end ) );				$result = json_decode( trim( $error_output ), true );				if ( empty( $result ) ) {					$result = $json_parse_failure;				}			}		}		delete_transient( $transient );		if ( true !== $result ) {			// Roll-back file change.			file_put_contents( $real_file, $previous_content );			if ( function_exists( 'opcache_invalidate' ) ) {				opcache_invalidate( $real_file, true );			}			if ( ! isset( $result['message'] ) ) {				$message = __( 'An unidentified error has occurred.' );			} else {				$message = $result['message'];				unset( $result['message'] );			}			return new WP_Error( 'php_error', $message, $result );		}	}

这个方法仅仅是WordPress官方出更新前的一个临时替代方式，PHP修改被回滚" width="751" height="223" />

1、

3、”主要以下原因：