Fatal error line 186 common.php

Right, so I moved my site from my friends account to my account.

Delete quick start html, as was advised.

Now this comes up when I go to the site-

[color=#FF0000]Warning: require(./includes/acm/acm_file.php) [function.require]: failed to open stream: No such file or directory in /home/lrcking/lethbridgeroadcrew.com/common.php on line 186

Fatal error: require() [function.require]: Failed opening required ‘./includes/acm/acm_file.php’ (include_path=’.:/usr/local/lib/php:/usr/local/php5/lib/pear’) in /home/lrcking/lethbridgeroadcrew.com/common.php on line 186[/color]

This is what appears on line 186 in common.php right now-

[color=#32CD32]require($phpbb_root_path . ‘includes/acm/acm_’ . $acm_type . ‘.’ . $phpEx);[/color]

What EXACTLY do I do?
I am not the coding junkie my friend was, I know enough to probably destroy the universe, and not much else.
I have the programmers notepad open right now…please…help…me…

Does this directory exist?