Hello, I took my MBP 2010 17" to McDonald's yesterday. I was able to connect to their wifi in the past but not yesterday. I tried to connect my iPhone 6s plus to their network but also failed. However, the girl next to me was able to use their internet using a newer computer. What happened? If my MBP is too old, then I should be able to connect to their wifi using my 6s plus. However, it failed as well. The McDonald's is just across a school building. In the past, I could connect to the school's wifi router from McDonald's. However, my Mac always connected to the McDonald's wifi router first. Is there a way to set the preference so that when the school's wifi is detected, my Mac would connect to it but I want to connect to the McDonald's network (sometimes the school's wifi signal is weak as it is across the street), I could do it as well.