1.0 Error

After updating the website to a new version of Drupal 7, the following error was printed on the web pages.

Notice: Trying to get property of non-object in block_block_view() (line 247 of modules/block/block.module).

2.0 Resolution

The error was resolved by the following steps.

2.1 Turn off block caching

From the Administration menu, Select Configuration –> Development –> Performance. Under CACHING un-check Cache blocks.

2.2 Modify block.module file

Go to the modules/block directory under the website root directory. Open the file block.module. Find the following code near line 247.

/**
 * Implements hook_block_view().
 *
 * Generates the administrator-defined blocks for display.
 */
function block_block_view($delta = '') {
  $block = db_query('SELECT body, format FROM {block_custom} WHERE bid = :bid', array(':bid' => $delta))->fetchObject();
  $data['subject'] = NULL;
  $data['content'] = check_markup($block->body, $block->format, '', TRUE);
  return $data;
}

Change the above code to,

/**
 * Implements hook_block_view().
 *
 * Generates the administrator-defined blocks for display.
 */
function block_block_view($delta = '') {
    $block = db_query('SELECT body, format FROM {block_custom} WHERE bid = :bid', array(':bid' => $delta))->fetchObject();
    if (!empty($block)) {
        $data['subject'] = NULL;
        $data['content'] = check_markup($block->body, $block->format, '', TRUE);
        return $data;
    }
}