Custom Presentation Size not retained with save

I am simply opening a presentation, then writing it out to a new location. No changes. No alterations. Code snippet:

using (PresentationEx pres = new PresentationEx(“original.pptx”))

The original presentation AND new presentation both show:
pres.SlideSize.Size.Width at 960.0
pres.SlideSize.Size.Height at 540.0
The SlideType is Custom.

The original presentation has a 16:9 ratio and 13.333" width x 7.5" height
After saving, the new presentation has a 4:3 ratio and 10" width x 7.5" height despite the sizes shown above.

Again, this is after changing nothing within the presentation. Am I doing something wrong here? Using version 7.9.0

EDIT - I also verified the same issue with version 15.2.0

Thanks for all help.

Hi Scott,

I have observed the issue shared by you and request you to please share the source and generated presentation. I will investigate the issue on my end to help you further.

Many Thanks,

Thank you very much for the assistance. I’ve attached two files, the original PPTX as well as the (unintentionally) re-sized version. These were generated using the latest version.

Please post your finding asap as I have clients waiting for a resolution.


Hi Scott,

I have worked with the presentation file using Aspose.Slides for .NET 15.2.0 on my end and have not been able to observe the issue. I request you to please verify Aspose.Slides for .NET 15.2.0 by creating a new sample application. I have used the following sample code on my end.

Presentation pr = new Presentation(path + “original.pptx”);
pr.Save(path + “original2.pptx”, SaveFormat.Pptx);

For your kind reference, I have attached the generated presentations s well that has same size as that of source presentation.

Many Thanks,

Thanks Mudassir, I will investigate and let you know my findings.