How To Resolve "Validation of viewstate MAC failed" Error

Sometimes when we I open my asp.net website, began using it, left for a while, and came back an hour later, when I resumed using it and did anything that caused postback, it immediately threw the "Validation of viewstate MAC failed" error. Unfortunately in order to re-create the error, I have to wait a while, which is very inconvenient for testing/troubleshooting. And this article is giving a very simple and easy solutions for the very inconvenient error that i got. It solves my issue right away.