For those like me who have been plagued by the <ppt>/<pptx> file type not supported errors in Blackboard (such as http://www.wecollaborate.com/forum/topics/the-ppt-file-type-is-not-...), I believe that I have a workaround.

I had Blackboard show me the Java console while the application was running and saw an error regarding the PPTHelper failing to load and that Blackboard couldn't find the VB5 Runtime to fall back to. Downloading the Visual Basic 5 runtime from Microsoft and installing it, has once again allowed me to load PowerPoint content from within Blackboard.

I hope that others find this useful as it's been driving me nuts for over a year now.

Cheers