Error message at site, and can't log into Opencart admin

When I go to my site, www.beefriendlyfibers.com , the two paragraphs at the end is is the error message I get. Everything was fine yesterday after I made some modifications. Ipage is telling me that it is a problem with scripting in Opencart (of course, because Opencart is 3rd party, they do not ever want to help. This was after I paid a concierge, and was set up with Opencart) Does this error message indicate that it has anything to do with Opencart? Thanks for your help. Oh, and the original message said line 19, if that indicates anything.

Warning: require_once(/home/users/web/b2284/moo.getfenomenoncom/Store/system/startup.php) [function.require-once]: failed to open stream: No such file or directory in /hermes/bosoraweb021/b1171/ipg.beefriendlyfiberscom/Store/index.php on line 20

Fatal error: require_once() [function.require]: Failed opening required '/home/users/web/b2284/moo.getfenomenoncom/Store/system/startup.php' (include_path='.:/usr/local/lib/php-5.2.17/lib/php') in /hermes/bosoraweb021/b1171/ipg.beefriendlyfiberscom/Store/index.php on line 20

what did you modify/install?

I didn't install anything new, or work on the site except within the administration panel- categories and products. I made a few changes to the home module, but, as I said, within administration.

And did you find what caused the error?