I have a PowerPoint Add in that create, modify and save presentations. Specific options for the opened presentation should be stored in this presentation file (.pptx) using Open XML, when i try to do this I get an IOException:
**System.IO.IOException : The process cannot access the file 'test.pptx' because it is being used by another process.**
This is a snippet from the code:
**
using (PresentationDocument pptPackage = PresentationDocument.Open(fileName, true))
{
// add options to pptx file.
}
**
Thank you.