The below visual basic code will apply a design theme template to all powerpoint files located in a folder.
Sub ChangeDesignTheme()
sFolder = “Enter Directory Path”
sFileExt = “*.pptx”
sFileName = Dir$(sFolder & sFileExt)
While sFileName <> “”
Set Presentation = Presentations.Open(sFolder & sFileName, msoFalse)
ActivePresentation.ApplyTemplate FileName:=”Enter file location of presentation template”
ActivePresentation.Save
ActivePresentation.Close
Set Presentation = Nothing
sFileName = Dir()
Wend
End Sub
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