I have encountered this problem with Powerpoint 2007 as well on a Toshiba laptop. One solution I found and I don't know why this works is to connect the computer online before you run the slide show. For some reason the computer must run some type of update. At first I thought it was Norton Antivirus but we removed that and it still did it. You can view all this activity in the event manager log. Every five minutes the computer tries to connect to the internet and that's when it dumps the Powerpoint show. After it connects then everything is OK. This issue is very annoying especially when you are giving a presentation in front of people.
I recently upgraded to Office 2007 and use Powerpoint for presentations at our local church. I've noticed that after a few minutes of starting a presentation that Powerpoint will stop the presentation and go back to slide view. I've also noticed this on a set of slides that are just set to loop continuously and change every 10 seconds. Is there some new setting in Office 2007 that I'm overlooking - very frustrating to have to hit F5 time after time. Also both of these presentations were from MS Powerpoint 2003 formats, I haven't tried creating a blank presentation to see if the problem still exists.
Thanks.

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