Probs installing 2.71 wp-admin/install.php on line 21

Having trouble installing WordPress Version 2.71. Getting this message:-

Warning: require_once(./includes/upgrade.php) [function.require-once]: failed to open stream: No such file or directory in /home/miscella/public_html/wp-admin/install.php on line 21

Fatal error: require_once() [function.require]: Failed opening required ‘./includes/upgrade.php’ (include_path=’.:/usr/lib/php:/usr/local/lib/php’) in /home/miscella/public_html/wp-admin/install.php on line 21

Unistalled 2.71 and installed 2.7 which worked.

Anyone else having those probs.