Excel 2007 encryption 2

[automaker]

What happens in an Excel 2007 workbook when a user clicks through the following; Office button, prepare, encrypt document.

It seems that the password entered becomes the password to open the workbook but is that all? Is the data within the workbook encrypted and if so, how does that improve security. This seems different from the encryption options offered in previous versions of Excel.

Thanks,

 

[genomon]

The encryption in Word, Excel, and PowerPoint 2007 basically turns your files into a mess that no one can read… unless they have the password. In fact unless you get the password right, there is no chance you can even open the file.

Maybe helpful:

http://thenewpaperclip.com/2008/09/29/how-to-encrypt-your-word-excel-and-powerpoint-2007-files/

Good links at the bottom of this page also.

Cogito eggo sum – I think, therefore I am a waffle.

 

[GlennUK]

Beware, encryption in Excel ( even 2007 ) is never 100% safe ... there are tools out there to crack this.

Cheers, Glenn.

Beauty is in the eye of the beerholder.

 

[automaker]

Genomon,
Thanks for the reply. Your reply actually gets to the heart of my question. If you need a password to open the file and the same password is used by Excel to encrypt the file, what is the benefit in the encryption? Both methods of protecting the file (password to open and encryption) are unlocked with the same key and at the same time. I am not seeing the benefit.

 

[automaker]

Glenn,
Agreed and thanks. If there is a lock, there is also a key.

 

[TonyJollans]

Password to Open" and "Encryption" are one and the same - they are not two separate functions and it makes no sense to consider them as such.

I have to disagree with Glenn as far as cracking encryption of 2007-format files, encrypted in Office 2007. If you use a strong password there are no tools out there at the moment that can break it in real time - that's not to say there won't be in the future, but, for now, it's pretty good, and the whole file is now encrypted, including the VBA project, which was not the case before.

Encryption of old binary format files, however, is not safe (even in Office 2007) - the default 40-bit key can be cracked instantly on a modern PC; if you do use it, you should use a 128-bit key and a strong algorithm, and even then you should be wary.

Enjoy,
Tony

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[xlhelp]

I haven't tried it, but you have five ways to protect your Excel files in 2007.

1 Through Office Button; Prepare
2 & 3 Under File Save as... dialog box, under tools, Password to Open and password to modify. [red]One of those may the same as the first one; haven't tried[/red]
4. Protect Sheet under the Review tab [blue]and[/blue]
5. Protect Workbook Structure and Winows

and then you have to keep in mind: nothing is safe

A man has only two choices: He can be right or he can be happy.

 

[automaker]

Tony,
Thanks and your statement about encryption and password protecting being the same thing is what I was thinking. So the process of Office button - prepare - encrypt is identical to Office button - saveas - Excel document - tools - general options - password to open? Is that what we are concluding from this?

 

[TonyJollans]

Automaker - yes.

xlhelp - although the other ways you mention could be considered levels of protection, it is only the "Password to Open" (however the dialog is reached - yes your #2 and #1 are the same feature) that leads to encryption of the file.

Enjoy,
Tony

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[automaker]

Thanks Tony.
This was confusing me on these two seemingly different paths that ended at the same point. Also, I understand the other passwords etc. offer minimal protection at best. Once the workbook is opened, the rest is basically just to prevent accidents.
Very helpful, thanks.

 

[GlennUK]

Hi Tony

I have to disagree with Glenn as far as cracking encryption of 2007-format files, encrypted in Office 2007. If you use a strong password there are no tools out there at the moment that can break it in real time - that's not to say there won't be in the future, but, for now, it's pretty good, and the whole file is now encrypted, including the VBA project, which was not the case before.

Thanks, I'd seen the banner adverts for Excel 2007 crackers, but hadn't bothered to research any further ... the small print tends to say that recovery may take months of computing time, and then only if the password is relatively short. Am much more informed now, thanks ===> *

Cheers, Glenn.

Beauty is in the eye of the beerholder.