Alternatives to checking against the system time
I have an application which license should expire after some period of time.

I can check the time in the applicatino against the system time, but system time can be changed by the administrator, therefore it's not a good idea to check against the system time in my opinion. 

What alternatives do I have?

Thank you
Alternatives to checking against the system time
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I have an application which license should expire after some period of time.

I can check the time in the applicatino against the system time, but system time can be changed by the administrator, therefore it's not a good idea to check against the system time in my opinion. 

What alternatives do I have?

Thank you