Wifi randomly turning itself off MacBook Pro
I feel your pain.  I had this same problem with my 2012 Macbook Pro. My WiFi would lose connection, and I would have to turn it off and then back on to regain the connection.  Then it started giving me the "WiFi not configured" message when I would turn it back on. Sometimes a reboot, or PRAM reset, or several reboots/resets would resolve it for a little while.

I will say there does not seem to be an easy fix.  Mine started having this problem when I installed Yosemite; my hunch (at least for my case which was very similar) is that is is a software/driver issue and not a hardware issue.  Call apple tech support.  

I will say that mine was out of warranty, but they still helped me; they put me in touch with their engineers to work on the problem, gave me software diagnostic tools to figure out what was happening, and eventually were able to resolve my problem. They went to great lengths, and I am no longer working on a computer that has this issue thanks to them.