Computers and Software : cpu experts, a question for you

why do differet machines running the same software sometimes have odd things happen like for example, a pre-paid internet dongle thats supposed to launch on startup wont on one machine running windows 8.1 even though the box that says open in startup is clicked, yet will work perfectly on another machine running windows 8.1?

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Trump/Pence 2020 Lets go for the win Bros!

Windows 8 is the biggest shit ever released. How appropriate that you would use it.