Retrieval of slide "history"

[Guest]

Is it possible to "go back" in a Powerpoint presentation and view slides that
have been deleted or originals of chaged slides?

Concretely, is this a security issue, where a someone might get the
presentation and find earlier confidential materials buried in it?

Karolien

 

[Sonia]

As long as you have "Fast Saves" turned OFF, there is no archiving of edited
items in the file.
--

Sonia Coleman
Microsoft PowerPoint MVP Team
Autorun Software, Templates and Tutorials
http://www.soniacoleman.com

 

[Guest]

Thanks!

Ok, but say I get a random presentation, can I go in and look for "previous"
slides. People so often just rework presentations. How can I check that
"archive"?

 

[Sonia]

I'm not sure that I understand the question, but if you open PowerPoint and then
open the presentation, you'll see everything that the file includes, even
skipped or hidden slides. Maybe if you tell us exactly what you want to do, we
might be able to offer some suggestions. Do you want to hide info from others,
or are you trying to find info in someone else's presentation?

 

[Guest]

My boss has ordered that no ppt can be distributed unless they are in pdf
format because: "It is possible to restore history" Essentially saying that
if I use a highly classified PPT presentation, edit it and delete all
sensitive information, save it and send it, that the person that receives
this ppt file can restore the history of the file and somehow view the
confidential info from a previously saved version.

I cannot find any confirmation of this, but I can also not disprove it.
That's what I'm trying to figure out.

Karolien

 

[Sonia]

There must be some reason that your boss has this idea in his/her head. It
could be hearsay, or it could be a misunderstanding of the composition of a
presentation file. I was never good at telling the boss, "You're wrong!" There
are however, other ways to protect presentations. See:

Password protect a presentation
http://www.rdpslides.com/pptfaq/FAQ00038.htm

 

[Guest]

So, in essence, as an expert, (you know I'm going to quote you ) you do
not think that it is possible to retrieve previously saved information from a
ppt presentation?

karolien

 

[Sonia]

If you're going to quote me then I'd like the wording to be crisp. "If you open
version 1 of a presentation and delete slides or objects and then save the
presentation as version 2, and if you do not have Fast Saves turned on, the
version 2 file will not contain the deleted data."

 

[Guest]

If I DO have "fast saves" turned on, how can I go about retrieving the
previously deleted data?

BTW, awesome website!

 

[Sonia]

I don't know that you could actually retrieve it, but you might be able to view
it if you opened the file in
a text editor.

 

[Guest]

I've made a test presentation, saved it, modified it and saved it again. I
then opened it in Word, Wordpad and Notepad, but none of them showed the
deleted content. Is there another text editor I should try?

Thanks for your patience with this. I really appreciate it.

 

[Sonia]

Isn't that the result you want? Did you have Fast Saves on? As I said, you
**might** be able to see it in a text editor, but you would need to know more
than I do about the internal PowerPoint format, etc. The data is there, in a
form that PowerPoint can read, but I'm not sure that a human can. Just turn off
Fast Saves and it becomes a non-issue.

 

[Tim Hards]

Hi!

Although you say your boss is worried about being able to restore
history, there should be an additonal concern. There might be
confidential data in the presentation that is not obvious, and which
might be missed out during a cleaning attempt.

Things that come to mind are: VBA code, unused master slides, notes,
text that is off the slide, data stored in shape tags, custom data
fields, names of items (accessible via VBA), items covered up by other
items...

Converting to PDF is probably a good safety step to ensure that things
like these don't get left in.

--
Tim Hards
http://timhards.com/

Chief Software Architect
Perspector - 3D Business Graphics for PowerPoint
http://perspector.com/

 

[Guest]

In general I would agree. But the issue came up because we will be
distributing conference procedings to a group of people. The only reason to
give them a CDrom with this info is so that a) they have the info and b) they
can use the info and individual graphics from this presentation in
presentations they use for their audience.

A way around the "history" is to start a brand new presentation, apply my
template and copy the content, not slides, from the other presentations,
giving me a clean document without any history or previous edits. It takes
about half a minute per page to this.

Thanks for everyone's input!

 

[Steve Rindsberg]

My boss has ordered that no ppt can be distributed unless they are in pdf
format because: "It is possible to restore history"

Do you have a spare $100 to lay on a bet that it can't be done? If so, you're in a
position to make some money fast. ;-)

Ask the boss to demonstrate this on a file that's been saved once you've turned the
fast saves feature off.

Come to think of it, if you haven't got the C-note and the boss is willing, I'll
front it and give you 25% when we win. I get to supervise the test.

It'd be worth that to find out how he did it if we're wrong. ;-)

Essentially saying that
if I use a highly classified PPT presentation, edit it and delete all
sensitive information, save it and send it, that the person that receives
this ppt file can restore the history of the file and somehow view the
confidential info from a previously saved version.

I cannot find any confirmation of this, but I can also not disprove it.
That's what I'm trying to figure out.

This kind of thing is almost impossible to disprove. It's always possible that
shreds of info get left accidentally in the file, but the same thing is potentially
true of Acrobat. Can the boss say with 100% certainty that it's not?

FWIW, if you can't get out of doing PDFs and are going nuts trying to preserve links
'n stuff, have a look at another pretty good bet, one we both win:

http://prep4pdf.pptools.com

 

[Steve Rindsberg]

Just to play devil's advocate:

A way around the "history" is to start a brand new presentation, apply my
template and copy the content, not slides, from the other presentations,
giving me a clean document without any history or previous edits.

How do you know this? You've no way of retrieving edited content from a normal
presentation, so how can you tell that it's not carried over when you insert
slides from the presentation into another one?

I'm not trying to be difficult, but if the boss wants rigorous proof, you have
to apply rigorous methods of testing. ;-)