Converting PPTX to image does not work on Windows 2012 server

Question

We have a requirement to convert downloaded PPT or PPTX files to image files. We developed this work locally with the following (POC code):

Application pptApplication = new Application();
Microsoft.Office.Interop.PowerPoint.Presentation pptPresentation = pptApplication.Presentations.Open2007(filePath, MsoTriState.msoFalse, MsoTriState.msoFalse, MsoTriState.msoFalse);
List<string> files = new List<string>();
for (int i = 1; i <= pptPresentation.Slides.Count; i++)
{
    pptPresentation.SaveCopyAs(serverPath + randomId, PpSaveAsFileType.ppSaveAsPNG, MsoTriState.msoTrue);
    files.Add(root + "Uploads/Slide" + i + ".PNG");
}
pptPresentation.Close();

Now that this code is deployed to Windows Server 2012 R2, I get the following error:

This error looks like a permission issue, and when I googled, I found several solutions that I tried with no luck, here are some of them:

• Installing an office on a server - it makes no sense to have an office on a server :( well, I installed and still get the same problem.

• Interop - Windows Server 2012, , https://www.microsoft.com/en-us/download/details.aspx?id=3508 2012 , , .

• qaru.site/questions/1059675/...,

• , Aspose, Spire ..

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Answer 1

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• " " C:\Windows\SysWOW64\config\systemprofile\Desktop (64- )
• IIS ApplicationPool 'ApplicationPoolIdentity' 'LocalSystem'.

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, :

Application pptApplication = new Application();
Microsoft.Office.Interop.PowerPoint.Presentation pptPresentation = pptApplication.Presentations.Open2007(Server.MapPath("~/tempslides/pptfilename.pptx"), MsoTriState.msoFalse, MsoTriState.msoFalse, MsoTriState.msoFalse);
List<string> files = new List<string>();
for (int i = 1; i <= pptPresentation.Slides.Count; i++)
{
    pptPresentation.SaveCopyAs(serverPath + randomId, PpSaveAsFileType.ppSaveAsPNG, MsoTriState.msoTrue);
    files.Add(Server.MapPath("~/tempslides") + "/slide" + i + ".PNG");
}
pptPresentation.Close();

, interop lib .

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