I don't know Joe. That DLL is not part of Hoster so it has something to do with the Videos obviously. Quartz.dll is a library with functions for DirectShow, a part of DirectX. So maybe you need to check your DirectX and make sure it is correctly installed.
If you run the Belarc Advisor it may tell you where the problem is. If need be you can download a free copy of the DLL file here:
http://www.dll-files.com/dllindex/dl...s.shtml?quartz