Giving Software a 'Trial Period'

[Peter T]

Hello,

I've written software (LabView executable) and I'd like to create a demo
version of it that will non-functional after a fixed period of time. I can
think of a number of ways to implement this. However, I was wondering if
anyone had any preferred methods or if there are any standard ways of doing
this.

Thanks,

Peter

[waldemar.hersacher]

I don't know how much your software costs and which license model you will use.

For low price, buy and use for ever software I prefer to write a key into the registry, when the software starts the first time and setting the date. Next start will check this key. This key will not be removed by uninstalling the product so this prevents using the software by installing again after trial period. Use a key and values which are not easily found by regedit. An advanced user will export the registry before installation, after installation and after first use so he is able to detect your mechanism. For a licensed version send your customer a reg file with a date far in the future or a special invalid date.

For high price software we use dongles from www.wibu.de
. They allow updateing the data local or over internet. So you can allow different trial periods, pay per year, pay per usage licensing models.

Waldemar

[mcclements]

I've been looking into writing to registry keys for this problem. Are there any examples of how to do this? I don't want to cause a serious error in my registry and stop my OS from operating.
cheers