How to protect an Excel file from being copied to external device?

[BELFRED6]

I have a file used by our employees through our local area network. Because that file has many functions and possibilities that took us a lot of time to create, I would like to protect this file so no employee can copy it to an external device without a password. It would be great, though, if the file could be exchanged or sent among employees as logn as it remains WITHIN our internal network.
Is it technically possible to protect an Excel file in a such a way?

 

[Ragnar1211]

It is not possible to prevent a file from being copied.

Your best bet is to put code into the file that checks to see if a certain file exits, if it doesnt, then have the macro self destruct the excel file.

 

[BELFRED6]

Yes, that's an idea.... Any idea where I can find such a code?

 

[navinaaaaaa]

how to do that?

 

[Willem!]

@ Gerry: couldn't a user simply bypass that selfdestruct-macro by manually disable macro's at startup?

 

[Ragnar1211]

Very true.

 

[Ragnar1211]

The real problem is that you can always copy and paste excel, so no matter how creative you get with your protection, there will always be a way around it if the user can open the files under "Proper" circumstances.

The best course of action: Get signed codes of conduct and confidentiality agreements with the staff. These should specify the ownership of software developed through the course of business.

However to impliment a intellectual property battle is not likely worth the cost.

 

[Stormseed]

@ Gerry: couldn't a user simply bypass that selfdestruct-macro by manually disable macro's at startup?

Force the user to enable macros:

http://www.vbaexpress.com/kb/getarticle.php?kb_id=578
http://www.mrexcel.com/forum/showthread.php?t=109769

 

[Ragnar1211]

Love it... evil thoughts coming on!

 

[Willem!]

Force the user to enable macros:

http://www.vbaexpress.com/kb/getarticle.php?kb_id=578
http://www.mrexcel.com/forum/showthread.php?t=109769

Neat! Didn't know that could be done.

However: I believe that NO file can be 100% protected from 'evil' users, there's always a loophole. Be aware of that.