Selling excel projects???

[Steff_DK]

I've made my first database for a company. How do I protect my work. Ca
I limit the time it will work, so they will have to pay for a licens
every year?

Any thoughts on the commercial side of all this programming?

Thanks

Stef

 

[JE McGimpsey]

Unless you compile your code (e.g., make a COM add-in), you're in for a
tough time. I've got one client who has about 10 different layers of
protection, which would keep novices out, and it still takes only about
60 seconds for a knowledgeable user (i.e., someone who can find and read
these newsgroups) to disable it.

You might look in the archives

http://groups.google.com/advanced_group_search?q=group:*excel*

for posts using "expire" as a keyword.

Compiled code can be fairly secure. Be sure to include a method for
renewing the license (e.g., an encrypted key) in the code.

XL2003 includes DRM, which requires a Windows 2003 Server to provide
access to the module. This would prevent use in XL97/98/00/01/02/v.X. I
have yet to have a client tell me that such a solution would be
acceptable, except possibly internally (but then none of my clients use
W2003 server, either).

Also, be careful: if you've already made the database for the company,
and you were contracted to do the work, the company already owns your
code, unless your contract specifies otherwise (at least in the US
jurisdictions I know of). If you're an employee, the same may apply,
depending on your explicit or implicit employment agreement - most
professional employment agreements that I've seen assign the rights to
*all* your related work to the company. Protecting it could be
considered fraud.

 

[JE McGimpsey]

Sorry, meant to add a line or two:

Compiled code can be fairly secure. Be sure to include a method for
renewing the license (e.g., an encrypted key) in the code. Do you have
Office Developer? It's hard to tell what will work best for you without
more information, but doing a date check with some algorithm that checks
the expiration date will likely work, though you may want to include
some way of externally flagging the expiration date to make it harder to
just set the clock date back.

Finally, make sure your client can at least access/export their data
after expiration. Completely locking out access is a good way to (a)
ruin your reputation as a developer, and (b) get yourself sued.