I live on a US sailboat right now off the coast of New Zealand. My Mac will only recognize power input from a land-based source. It will not charge from either a 110 or 220 outlet on the boat. Any suggestions?

For any that have been following this dialog, I have worked out the problem to the computer charging on the boat. After learning nothing of value from the Apple Store tecnician in Auckland, I called 2 computer repair shops that listed Apples as computers they worked on. Both listened to the symptoms, asked pertinent questions and told me that somehow noise was getting into the line on the boat. The simple solution without bothering to find out how, where or what the noise is, was buy a Spike Buster for a mere $30.00 NZ. Only the master electrician at the marina knew what a Spike Buster was, but he said a Surge Protector might work. I ended up buying a small Surge Protector that stated it protected against spikes and cancelled out noise in the line. ($14.99 NZ on sale) Plugged it in on the boat. The MacBookPro sighed in relief and immediately started charging as it should. Three weeks later, an 1,100nm passage, we are now in Vanuatu, and the computer is going strong.

There appear to be a few more boats out there with a similar problem. This simple fix worked for us.

Also, we found a boat whose owners had one of those MikeGuyver kits for their 2 MBPs on board. We tried it on our boat, and the computer started charging as it should. Once back in the States, I will be ordering one of those so that I have both options available.

Hope this will help those boats that have written in with the same charging problem.

We are a US-wired boat: 60hz

I presume you mean the Surge Protector. It is by Surge Shield. Model # M7800-1.

Sorry. There were so many complicated and technical responses to my problem that were beyond our capability to input on this boat either due to cost or availability that I stopped reading many of them. I wanted a simple, uncomplicated fix to the problem, and that is what I finally received from the 2 technicians at 2 different computer repair stores in Auckland, NZ. In short: "You have noise in the electric current on the boat. Go get a Noise Buster." That's all we needed to know. Our little Surge Protector is doing the job.