Hi,

I'm trying to add some basic security to a workbook, but which will check if
the user (via Application.UserName) exists in an Exchange PDL, and if it
does, then give them access

This is a template workbook and therefore saved thousands of times as
different file names... I need the PDL check to run live, so I can add more
users by adding them to the PDL, giving new users access to all previously
saved workbooks from the template and the template itself...

it's easy enough to imbed a list of users into the workbook/code, however,
adding a new user this way will only effect new files created from the new
template from that point on - the new user would not be able to access
existing files (not good)...

Before you ask, I cannot use the Rights Management functionality in Office,
as we do not have it installed, and I'm using additional code to render the
workbook useless unless macros are enabled...

Thanks in advance...