ShaunP. wrote:
This is a little dissapointing to hear.

How is it that Microsoft hasn't taken the time to implement this? Being the
the biggest mainstream spreadsheet application without any reliable security?
Countless businesses are at risk of compromise with just a few google
searches?

There must be someway more reliable and secure.

If you are that concerned about protecting intellectual property then
you probably will have to put the critical calculations in a compiled
encrypted external DLL. Even then it can still be disassembled by a
sufficiently determined adversary.

You might want to experiment with some of the available password
crackers to see how easily they can break into protected VBA code. My
instinct is that for a suitably awkward choice of long password that
isn't in any dictionary and uses the full range of characters the Excel
security isn't brilliant but it will discourage most people.

My recollection is that they can break into worksheets very quickly, but
that VBA puts up a bit of resistance. YMMV

Somebody described a fairly devious way to trick XL into not displayiong
the project code window in a thread fairly recently. I haven't tried it.

Given how bad Excel 2007 is in other areas like graphics its security is
better than you might expect.

Regards,
Martin Brown