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Tom Ogilvy Tom Ogilvy is offline
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Default Security - Delete File

any code based solution is easily defeated by disabling macros before
opening the file.

Sheet protection is very week. Free code or links to free code to break
this protection is posted almost daily.
--
Regards,
Tom Ogilvy


"Anthony" wrote in message
...
Thanks for your reply Tom,

This file is actually a POS program, written in Excel with a lot of
formulas, it holds sheets with a lot of costings and sensetive

information,
but holds no actual data, it is used to create an invoice.

All the sheets with the sensetive info are hidden, and all the formulas

are
hidden, and password protected.

So the actual file is usable with out needing a file password, but in

order
to change the formuals/pricing a password is required(which the programmer
has).

But as I am aware that password crack programs are quite easily available,

I
dreamt up the idea that maybe it would be possible to write into code

(maybe
in an Autoexex, if it exists) something where it looks at the machine ID
when the workbook is opened, and if it is not a specific machine name(hard
written into the code) the code could delete the workbook or certain

sheets
within the workbook, this way if a staff member were to copy the file and
take it home, it would not funtion correctly as their computer name would

be
different to the one hard coded into the Module.

I know no system is fool proof, but thought this, if possible, could help.

Should I stop dreaming, and just run with password protection? :-)


"Tom Ogilvy" wrote in message
...
Copying a file is a Windows activity. It has nothing to do with Excel.
You
can just go to windows Explorer and copy the file. If you password
protect
it, then at least if they copy it, they can not get into it easily
although
there are password cracker programs that can defeat the file password.
(but
if they use the file at work, wouldn't they need to know the password?).

You might want to put key information in a database and have the file
query
that database to get the information. Set it up so the information is

not
stored in the file. Any approach is not going to be foolproof, so what
measures you take would depend on how sensitive the information is.

Perhaps you can put the file on a single stand alone computer and

control
access to the computer. If you don't want it copied, controlling access
to
the file would be the most robust.

--
Regards,
Tom Ogilvy



"Anthony" wrote in message
...
Hi,

I have a file created in Excel, and I have been asked to secure it in
some
way to stop staff from copying the file and taking it home.

I know I can password it, which is a start but I was wondering if it is
possible to have Excel, using VBA code, look at the machine id and if

it
isn't "XYZ" have it delete itself.

I have no idea if this is at all possible as I am not very literate in
VBA
Code.

Any Help/Suggesstions would be greatly appreciated.

Thanks in advance,
Anthony.