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Question

Hey guys,

 

I just wandering to find a solution please help me if someone knows the answer.

 

I am creating a windows application and want it to non functional after one month. So how can i achieve this ?

 

Following are my findings and i need a good solution. 

 

1. Cant use system datetime(any one can change system datetime) .

2. Cant use static time because user can close and start application.