demo version of distributed program

[Elio Fungi]

Hi,
I want to distribute a demo version of a CVI executable: it should run
10 times on the user's computer and then show a message like "purchase
license" or someting similar. How can I implement this counter?
thanx

[Jattie]

I would create a hidden registry key. There is CVI FP even to write them and in order to "hide" it simply include a new line character (/n) in the key string.

This work really well and the only way to remove the string is if you know were to find it then.

If you need more detail let me know and I'll dig out some code.

[JuanCarlos]

Hi,

I guess it all depends on how much you want to protect your application. Using a registry is a great idea, however if you have a large distribution of you app, a simple port monitor could spot the trick.

If you feel it's woth it you can use a hardware dongle, if fairly inexpensive now and should be relatively easy to implement. Here is a link to a company that I've seen other customers working with.

Another option is have the application record in your server the number of times that has run so far. The down side is that you must have a public server allways running, but this gives you the oportunity to get a bit more info on who is using the demo.

I hope this helps.

Regards,

Juan Carlos
N.I.

[test_man]

Looks like I am going to need this.

Are there any other way/better way of doing this other than writing to registry?

Does user need to be an admin for CVI application to write registry value?

Jattie,

Can you please post your code if possible?

Thanks.