I am using the microsoft.interopt.powerpoint dlls in a website. I'm using them to take powerpoints and convert them into images to show in the website. I have this working fine when I run it in VS, however, when I moved it to the default website, it doesn't work. I don't get an error, and it can create the folders it needs to just fine, but it doesn't create any images. I've tried changing permissions to full control for everyone to rule that out. I also have tried running the app pool under the local system, and administrative user. The only thing I can see is when I run procmon and try to create the images I see a FAST IO DISALLOWED. However, I see that error when it works running under VS. When I do the same running the site under VS, there are 1000s of events calling the powerpoint.exe file (this is when it works). I gave the site full trust, by changing it to local system, and also by setting it in the web.config. Does anyone have any ideas on why I'm having this issue?