Please upgrade to 2.3 here.
The 2.2 and earlier branches are no longer being updated.
Fatal error: Class 'ReflectionClass' not found (solved)
I have this problem after a fresh upload successfully adding DB info and getting to the dashboard. Go to the forum however:
Fatal error: Class 'ReflectionClass' not found in /htdocs/thegreathimalayatrail/forum/library/core/class.controller.php on line 782