Hi and welcome to JustAnswer.com. My name is XXXXX XXXXX I will assist you with your issues.Please open PowerPoint 2011. Then do a update check. update it to 14.1.2
Or you can use this link to update
Microsoft Office for Mac 2011 14.0.2 Update >
Sorry wrong link
This link is for 3 updates for your Mac Office 2011:http://www.microsoft.com/mac/downloads
For those 3 updates, you only need to update SP1 first then 14.1.2.
Ignore the 1st update.
After those updates installed, please restart and test your PowerPoint files again.
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