Hmm... Are you using the most recent release (OJS 2.1.1)? What happens if you go directly to the installation URL, e.g. http://www.my-server/path/to/ojs2/index.php/index/install
? (If you've turned on disable_path_info, let me know and I'll give you a different URL to try. Otherwise, the above should work.)
If that doesn't get you anywhere, try turning on show_stacktrace; post the output here (changing anything you don't want public) and I'll see what I can do.
Open Journal Systems Team
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