Move Gallery to another directory and got this error. Please help

I move Gallery from one directory to other. I got this error, not sure where to fix? Please help, Thanks.

Warning: require_once(/home1/photoma2/public_html/G2/gallery2/modules/core/classes/Gallery.class) [function.require-once]: failed to open stream: No such file or directory in /home1/photoma2/public_html/G2/gallery2/bootstrap.inc on line 33

Fatal error: require_once() [function.require]: Failed opening required '/home1/photoma2/public_html/G2/gallery2/modules/core/classes/Gallery.class' (include_path='.:/usr/lib64/php:/usr/lib/php') in /home1/photoma2/public_html/G2/gallery2/bootstrap.inc on line 33

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