I have added an AutoNav block but get this error:

Warning: include(/home/rdpcorg/public_html/concrete5.6.1.2/concrete/blocks/autonav/view.php) [function.include]: failed to open stream: No such file or directory in /home/rdpcorg/public_html/concrete5.6.1.2/concrete/core/libraries/block_view.php on line 311

Warning: include() [function.include]: Failed opening '/home/rdpcorg/public_html/concrete5.6.1.2/concrete/blocks/autonav/view.php' for inclusion (include_path='/home/rdpcorg/public_html/concrete5.6.1.2/libraries/3rdparty:/home/rdpcorg/public_html/concrete5.6.1.2/concrete/libraries/3rdparty:.:/usr/lib/php:/usr/local/lib/php') in /home/rdpcorg/public_html/concrete5.6.1.2/concrete/core/libraries/block_view.php on line 311

what to do please?