Can someone please explain why all of a sudden it says I have no airport card installed? and how i can rectify the situation? Please and thank you!
Seems your physical card may have become UNSEATED, or may have become defective.
If you have a close by ARS, I'd have a diagnostics carried out at the bar.
Try resetting the SMC.
Yes, SMC may save an unneeded trip (if we get lucky here). Also may want to do a PRAM reset as well just to not question outself later.
At least they are simple tests.
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