How secure is the "lock cells" function?

[Guest]

My task is to send an excel document with importatant information that
shouldn't be changed to an external viewer. I wonder how secure it is to lock
cells/documents in excel compared to for example make a pdf-file with Acrobat
Adobe? Is it easy for someone to go "behind the scene" and change the code in
order to unlock the cells?

 

[Vasant Nanavati]

I wonder how secure it is to lock
cells/documents in excel

Not very.

Is it easy for someone to go "behind the scene" and change the code in
order to unlock the cells?

Yes, for any knowledgeable Excel user.

 

[CarlosAntenna]

If the recipient does not need the spreadsheet functionality to change
numbers or play "what if", it would be far better to send a PDF document.
Cutepdf is a free pdf writer. www.cutepdf.com

-- Carlos