I am in the need to have a version of my software that will only run for a limited amount of time, let's say 20 days.
I am quite unsure how to accomplish this in a safe matter.
I've been trying to find information on the Internet but was not very successful so far.
How do I go about this?
I guess I could just write a value to the registry or some hidden file when the software starts, and repeaditly check this value against the system time.
I'm not too worried about the system being changed as this software will run on servers, very unlikely that people are going to mess with that.
However I am worried that people will modify the information I keep that records the original start of the software, be it a hidden file, registry, ...
I want to make sure that people are unable to extend the period in a easy fashion, I would also like to make it as difficult as possible (reasonable though) for crackers to crack it.
I'm willing to raise the points for great answers.
Thank you !!!