Licensing Implementation

Any ideas on implementing licensing expiration for a piece
od software being sold i.e

Say, a customer gets the piece of software, we
get the current date and time and store it in some hidden area and a year later, make the app inactive if license is not renewed (Would prefer not to keep an internal clock

if at all possible)

though the client may change the computer time...
and stuff like that

Any great ideas appreciated....


This is the first time...

Try:
http://www.activelock.com

Thanks...

But... Would prefer to implement my own

Store the installation date in the Registry as well as a "temp" date everytime the App loads. This way, if someone tries to change the time, we would know, hence, it enables us to lock the app.

For example.

Code:

---

If ThisDate < TempDate Then
    'The Date has changed
Else
    'Everything is fine
End If

---

[Edited by Megatron on 08-29-2000 at 04:10 PM]

Shouldnt it be more like this??

Code:

---

If RightNow < FirstDate Then
    'Date Has Been Changed, So Do Stuff
ElseIf  RightNow - FirstDate = 30 Then
    'Its been 30 days
Else
    'Ok
End If

---

Because isnt TempDate changed everytime the program loads?