Problem with Powerpoint

I have a large powerpoint file that was over 100 MB.

Somehow, I recently opened it and now its only 50 MB. Many of the pictures I had on it are missing.

I had deleted some of the pictures I used to put in my Powerpoint, but that hasn’t affected other presentations I had where I also deleted the pictures.

Is this some security problem with Powerpoint 2010?

I don’t understand how all these pictures are missing. I had over 1000 slides on it, and now most of the images are missing.

Could someone please help me. I’ve searched for answers, but can’t find a solution.

Specifically, where the images were there is now a message on each slide saying “The image part with relation ID rid2 was not found in the file”

This seems to be a well known bug of Powerpoint, I did not find any solution.
Sorry.

Not related to Avast though.

See if the following is of any help to you:
http://community.ispringsolutions.com/viewtopic.php?f=9&t=786

Does anyone know how in Windows 7 to change the file type?

For example, to go from .ppt to .doc or something like that? When I try to do that, it just goes AcmeFile.doc.ppt. In otherwords, its still a .ppt file.

What do you mean: “change filetype”?

If you try to change the extension from “ppt” to “doc” (even though that makes no sense), you have to make sure that in Windows Explorer you can see the extensions.
Go to Explorer → Extras → Folder Options → View → Uncheck “Hide extensions of known filetypes”

Changing the file type from ppt or pptx to something else, make the file unusable.

Yes:

;D