PowerPoint suddenly can't open or save files
A windows update released by Microsoft in April of 2006 conflicts with several software packages.
Result: PowerPoint and some other Office programs may not be able to save or open files.
See the explanation and find a fix here:
Problems in Windows Explorer or the Windows shell after you install security update MS06-015
If your computer is sometimes connected to a network or you use removable drives, see this.
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