Mike9900 wrote:
How can I get the real system date/time if the user fakes the date, for
example by setting the system date back.
I see from the other posts you are talking about trail version software.
IMO, the only thing you can do is have the software "phone home" when
it starts. The first time it runs you record the date/time and user
key. At each startup you "phone home" to see if the software can still
run. After the trial period, that username/key can no longer be used.
Of course there is the issue of will your users accept your software
"phoning home" every time it starts up? I personally won't use software
like that. It all comes down to what you think your users will put up
with in a trial version.
There really is no way to prevent a determined user from running a trial
version multiple times. For example, if I _really_ wanted to run your
trail version without paying, I could use VMware or one of the other VM
apps to run your software and just keep resetting the virtual machine to
a state before expiration.
Have you thought about offering a reduced functionality version instead
of a timed version? All the cool features that someone will be willing
to pay for go in the full version. You give the users a sample with the
limited functionality version and not worry about trying to only allow
it to run for 30 days or 30 startups.
Jim
--
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You roll an 18 in Dex and see if you
don't end up with a girlfriend
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JimD
Central FL, USA, Earth, Sol