Store a back-up copy of your workbook without the following code. Then set a
future date for the workbook to selfdestruct with:

SelfDestructDate = 7/4/08
If Date = SelfDestructDate
For Each Sheet In ActiveWorkbook.Sheets
Cells.Clear
Next
End If

If someone steals a copy of the workbook, it will only work until the date
you set.
You will just have to remember to go in and reset the date periodically to
keep from losing current data.


"anon" wrote:

Hi all,

I have read through some past posts on this subject however am a
little stumped. If anybody could point me towards some resources
(preferably without lots of technical wording) where i can learn more
it would be great.

I've built a large wb used in an industry where the sheet
(specifically the functions / code & formula) would be worth a lot to
other companies. My company has a reasonably high turnover of staff
and it is not unusual for staff to take valuable wb like these with
them to their new role. However they need a copy of the wb whilst in
the company.

I need to build some super security into the sheet. My original
thoughts were to 1. Allow the sheet only to be opened on provision of
a pin 2. allow the sheet to only open until a certain date (or number
of opens) before the pin is required again 3. during this period of
time allow the sheet only to work on a certain computer (based on the
computer name) so if the sheet was transferred to another computer the
pin would be required again

I have read some posts saying that building this functionality within
excel is fairly pointless as would be cracked reasonably easily,
however i am unsure where / on what prog (i have no experience of
coding outside of office applications) i would write this and how i
would call it with my wb.

All help and suggestions very much appreciated. Thanks, K