You should realize that nothing you do will absolutely prevent a
somewhat educated user from opening or using your workbook after the
time you specify.

Using a macro is an OK idea, but if the user doesn't enable macros
(e.g., has XL's security level set to High), the macro will never fire.
A frequent suggestion is to hide your data sheet, leaving a sheet
exposed that tells the user to enable macros. Then in the Workbook_Open
event, unhide the data sheet and hide the "splash" sheet. This also
requires that you hide the data sheet in the Workbook_BeforeSave() event
(or try to prevent saving altogether).

And of course, nothing would prevent a user from copying your data and
pasting it into an unprotected workbook.



In article ,
"Chris" wrote:

thanks guys, I cant claim to understand how to achieve it right now but I am
now looking in the right direction and will have a go! any more ideas -
especially those more closely related to my ability - greatfully recieved.