Initializing throws System.NullReferenceException:

hi all.

I am trying to open a ppt doc with the following line of code
.
Aspose.Slides.Presentation pres = new Aspose.Slides.Presentation(@“C:\Documents and Settings\chrisz\My Documents\ppt\usability.ppt”);

and then i get the following stack trace

System.NullReferenceException: Object reference not set to an instance of an object.
at Aspose.Slides.Table…ctor(Slide parent, ಅ frame)
at Aspose.Slides.Slide…ctor(Presentation parent, à´– slide)
at Aspose.Slides.Presentation.à ´(ၸ ੝)
at Aspose.Slides.Presentation…ctor(Stream stream)
in c:******************:line 48

whats wierd is this is not the case with every ppt file i use.
some files work fine when opening and some files just never get parsed by aspose and that error is thrown at initilization

any idea? thanks

Dear Christian,

Please attach the problematic presentations. Sometimes, it occurs because of corrupt presentation. If you open them in MS-PowerPoint and disable its Allow fast saves checkbox under Options – > Save As and then save it back with different name, then they could work fine.

Also, are you using the latest version of Aspose.Slides 2.8.6.0 for .NET?

i have this same problem uploading powerpoint presentations and i am using the latest version of aspose 2.9.0.0:

[NullReferenceException: Object reference not set to an instance of an object.]
Aspose.Slides.Table..ctor(Slide parent, ૝ frame) +3043
Aspose.Slides.Slide..ctor(Presentation parent, ୬ slide) +5886
Aspose.Slides.Presentation.ਬ(๤ ਭ) +7449
Aspose.Slides.Presentation..ctor(Stream stream) +317

Please attach the presentation causing this problem.