To resolve the issue, follow these steps:

For .PPS files (Microsoft PowerPoint Slideshow)

 

  • Click Start, type regedit.exe and press ENTER
  • Navigate to the following branch:

HKEY_CLASSES_ROOT\PowerPointViewer.SlideShow.11\shell\Show

Right-click Show and click Rename; Type the word Open so that Show is replaced by Open command

*       If you have PowerPoint Viewer 2007 installed, repeat the above steps in this key, as well:                  

HKEY_CLASSES_ROOT\PowerPointViewer.SlideShow.12\shell\Show

*       After changing Show to Open, close Registry Editor Window.                           

*        

For .PPT files (Microsoft PowerPoint Presentation)

*       Click Start, type regedit.exe and press ENTER

*       Navigate to the following branch:

HKEY_CLASSES_ROOT\PowerPointViewer.Show.11\shell\Show

*       Right-click Show and click Rename

*       Type the word Open so that Show is replaced by Open command

*       If you have PowerPoint Viewer 2007 installed, repeat the above steps in this key, as well:

HKEY_CLASSES_ROOT\PowerPointViewer.Show.12\shell\Show

*       After changing Show to Open, close Registry Editor window.