Unchecked Out of Box Experience (OOBE) warning

[petrus]

I come to ask this question in order to avoid basic errors in building the system. I can't understand the warning above very well, it said that I can change the file extension, but I didn't understand for what purpose, could anyone tell me more?And does this "out-of-box" option below, if unchecked, interfere with anything? for example in the next steps, registration drivers unattended installation and post installation,So doing this 2nd step, carefully removing components, I came across these two options and I would like to understand them better if possible