I was checking out the Online Training Video for What's New in PowerPoint
2007 this morning, and the video plus its supporting audio was working just
fine.  Then I moved around in the training course offerings, to see if I
could find one for people who work with / for me who need an introductory
course on PowerPoint 2007.  For a while the video plus supporting audio kept
working just fine.  Then something changed.  Now it is only an hour later on
same morning.  I have not rebooted my computer.  I can still get the video
for any course, but cannot get the supporting audio at all.  Equally
frustrating, the process which I used for self-help search of Microsoft HELP
in Office 2003 has changed so much that I cannot find the area of Office 2007
where I might be able to learn what has gone wrong with the training audio.  
Primary question -- why did training audio first work, and now not work?  
Second questionary -- where do I go & how do I learn to use Office 2007 HELP,
so that it will become as useful and easy to use, as was Office 2003 HELP?