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Can't extract text from unprotected PPT using IFilter

I have a requirement to remove password protection from a PPT (using a known password) and then extract text from it using the Microsoft IFilter utility filtdump.exe.

I can successfully remove the password, but filtdump.exe can’t extract text from the PPT until I resave it using PowerPoint.

This is the code I used to remove the password (with Aspose.Slides 4.0):

Presentation presentation = new Presentation(filePath, new LoadOptions() { Password = password });
presentation.Password = null;
presentation.Save(filePath, SaveFormat.Ppt);

I have attached four files:

  • the original password protected PPT (password = 123)
  • the PPT I unprotected using Aspose
  • the PPT I unprotected using Aspose and then resaved using PowerPoint
  • filtdump.exe command line utility (the syntax to use is filtdump “filepath”)

Command line output:

filtdump "1. The password is 123.ppt"
Error 0x8004170b from IFilter::Init.

filtdump "2. Unprotected by Aspose.ppt"
Error 0x8004170b from IFilter::Init.

filtdump "3. Unprotected by Aspose and resaved with PowerPoint.ppt"
This is a PowerPoint Presentation!

Hi Reuben,

Thanks for inquiring Aspose.Slides.

I have worked with the presentation files shared by you using filtdump.exe and have not been able to reproduce the issue shared by you using Aspose.Slides protection removed presentation. I have just verified your set of presentations in Windows 7 x64 and Windows XP x86 and have not been able to reproduce the issue. For your kind refernece, I have attached the snapshot of my investigation as well. Can you please reconfirm the presentations on your end.

Many Thanks,

Hi Mudassir,

Sorry for not getting back to you earlier.

I have attached a screenshot showing my results in Windows 7 x64 and another screenshot from my colleague’s Windows 8 x64 machine. We both get an error for the file “2. Unprotected by Aspose.ppt”, although we have different error codes.

I am using Office 2007, although I think the PPT IFilter is included with Windows.

Kind regards,


Hi Reuben,

I have observed the issue again on my end and like to share that on 32 bit version of Windows XP, I have not been able to reproduce the issue. For Windows 7, I have been able to observe the problem and have created an issue with ID SLIDESNET-33837 in our issue tracking system to further investigate and resolve the issue. This thread has been linked with the issue so that you may be automatically notified once the issue will be resolved. I hope you have used Aspose.Slides for .NET 6.8.0 on your end for your investigation.

We are sorry for your inconvenience,