How to digitally sign a power point presentation?

I just found that there is an option to genearte digital signature in the power point. You click on the  office button and select prepare-> Add Digital Signature.

On clicking this, you will get additional forms with which you can generate a digital signature. The signature is visible on the signature window.  or you can view by prepare -> view signatures

Now with the digital signature, you can verfiy the certificate credentials of the person who generated the digital signature. Also, the presentation cannot be modified. You either need to remove the signature or save the file with a different file name to edit the presentation.

Warm regards

CRSK

I suspect that if you're seeing any options for signatures during this process, it's because you already have purchased a digital signature or have generated a self-signing signature at some point.

There's a form of Digital Rights Management (DRM) available in some versions of PPT (I think it might be only the ones distributed under corporate licenses ... bulk purchase, that kind of thing), but that also requires a server on the internet/intranet and special software to handle DRM authorization.

If I remember correctly, there's some way to grant privileges to people outside the organization, but that makes a few extra hoops for the recipient to jump through in order to open a protected presentation, and if they don't have an internet connection, they're unable to open the presentation at all.

I imagine that it can be quite useful within an organization that has the necessary resources, but for individuals and small businesses, it's not practical.

It's hard to get good information about it because people who have it are (obviously) seriously concerned with security and probably don't want to share.  Those of us with the freedom to volunteer here don't need DRM, or if we do, can't afford it.

As to PGP encrypting the file ... yes, that's the idea.  But with the shared key, the recipient should be able to decrypt it, no?

I tried using PGP:

http://www.pgpi.org/

After downloading the file gnupg-w32cli-1.2.2.zip  and installing it, I tried generating digital signature.

With this tool, I created my encryption key. Then I could generate the digital signature.

To generate digital signature, you run following  on command line:

gpg -s file

You can verify the signature by

gpg -verify file

However, the problem here is that the power point file will also get encrypted in the process.

Other option is to use :

gpg -s -o signture_file  presentation_file.

This statement when executed will create a separate signature file. But now you have two files to deal with.

I was under the impression that higher version of Power point may have inbuilt mechanisms for

generating the digital signatures.

Warm regards

CRSK

I'd check with companies like Thawte, Verisign and so on to see what they offer in the way of digital signing products.  I know that they have programs and related services that allow you to digitally sign the VBA code within PowerPoint and other Office files, but I'm not sure about the files themselves.

If that's not possible, you could also create a self-extracting ZIP file (ie, an EXE), which could be signed, or an installer EXE (signable) that installs one or more PPTs and other files on the user's system.