I have PowerPoint 2003. And yes I have Internet Explorer 6.0 installed.
Also, in the Tools | Options | Web Options | Browsers tab I selected
"Microsoft Internnet Explorer 6.0 or later". But for whatever reason,
Powerpoint is not making the connection between the two.
That option sets the type of HTML PPT generates (ie, for compatibility with older
browsers). I don't believe it affects which browser PPT actually launches for
previews.
Has me stumped, at least for now. But ...
1) Could PPT be assuming that MSIE's in a specific location?
Here, the preview feature works, and MSIE's in:
C:\Program Files\Internet Explorer\IEXPLORE.EXE
(I rightclicked the IE icon and chose Properties to find this quickly)
Where's your copy hiding out? Someplace different by any chance?
2) Could your copy of MSIE be messed up in some way?
Does it work ok normally?
Does it work ok if you doubleclick an HTML file, say, on the desktop?
3) If no joy and you want to do some serious digging:
Mark Russinovich's Sysinternals utilities on MS's site includes Process Monitor
which lets you watch registry and disk accesses.
http://technet.microsoft.com/en-us/sysinternals/bb545046.aspx
You might want to fire it up, halt all logging, clear the log, then switch to PPT,
get everything ready to go, switch back to Process Monitor, start logging, then
fire off the preview in PPT.
With any luck ProcMon will show you what PPT tried to do (and failed to do).