We have a step by step process in which the user clicks "Next" to continue on with their step. I know that "previous" is the obvious label, but wouldn't "Go back" be a bit more friendly/human? Next/Previous sounds like controls for a music player, which this is not it. This is a step process to installing a system.
Would another alternative be "Go back/continue"?
Be as contextual as you can be. Button labels should indicate clearly where the user will go if he/she clicks it.
As for the options you suggested, "Go back" sounds too absolute, it feels more like a "cancel", "never mind". "Previous/next" is OK, just not the most clear it can be.
So if your system is a step by step flow, use labels like "last step" and "OK! Next step".
You can go further and label them with the steps number/name. "Back to step 2" or "back to install options".
"Previous" is obvious choice here as "Go Back" gives a sense of feel that app is asking/highlighting user to go back where going back to previous screen should be option not mandatory!!
