Bumping this question as I'm experiencing the same issue. The powerpoint is trying to launch, and it won't run due to some security setting. Did anyone figure this out?
It looks like it's taken the ppt file from the MagicInfo server, and placed it on the D: of the display in a a temp folder- D:\Screen\AC46E948-4B98-4F14-B458-5949AE7CC3C6. Once I navigate into that folder I can see my ppt file and can launch it independently with no issues. It looks like it's having an issue with IE security, so I tried to open the file through IE on it's own and I didn't have any problems. I reset the security to low and tried with EWF off. Still no luck. I'm using Powerpoint Viewer 2007.