My MacBook Air was no longer charging when plugged in, despite the battery icon claiming to be normal when I hit option/click. I went to the Genius Bar at Conestoga Mall in Waterloo, Ontario, where I waited 2 hours for an appointment.
The tech diagnosed the issue as the adapter no longer functioning and recommend I buy a 60w replacement (for the same price) for my 45w one. He had managed to get my laptop charging again at the store on his own adapter/cord. I followed his suggestion, and got my laptop home to the discovery that it was not charging after all. I went back the next day, where tech #2 ran some more diagnostic tests which ruled out several options, and she offered to refund my money for the adapter, and suggested that I could leave the laptop with her (this was Friday afternoon) or else return it to the store on Monday for 72-hour turn-around with an engineer.
This was now four hours spent at the Apple store, unsuccessfully attempting to get my laptop fixed. I went to a local Mac repairman (Mac Repair Man, on King St. in Kitchener) next.
Ahmed was able to diagnose the issue (battery component not working), fix it, and told me that the 60w adapter is actually having to adapt to the lower power current of my 45w laptop, so he traded me an almost-new 45w adapter for the new one I had just bought at Apple. I won't be returning to the Genius Bar.