Apple Support Forums:
- "I have cleaned the dock with compressed air, vacuum, toothbrush, and whatever other small things I could get my hands on."
- "Make sure there is no lint, moisture or other debris in the dock connector port on the iPhone."
- "Get a hair dryer and run the air through the connections on the top (remove your SIM ) and bottom (the part that plugs into the docking station) of your iphone for 5-10 min. Take care not to over heat the iphone too much!"
- "I had the exact same problem with my 1st iPhone. I took it back to the apple store and they replaced it right away."
- "A while back a coworker of mine told me he had to pop out the sim and put it back in to fix that error on his phone. I dont see how that could be the cause but what happened in his case was that he dropped his phone and that message came on. Reseating the sim fixed it in his case (maybe it got knocked loose). Might be worth a try."
- "I've also seen reports that plugging and unplugging headphones in will remove this issue. YMMV."
- "I have the same problem. After having the iphone in my bathroom the message appears almost every 4 seconds. I think some condensate got into it."
- "Finally found on a Apple forum that lint can build up on the connector, dock, or cable and cause this error to pop up all time. Try cleaning the connector using keyboard air spray or was the cable and connector pieces. That should do the trick."
- "spent about five minutes with a needle cleaning out the dock and the dock connector. I also blew on them a lot. Problem solved. I would assume if certain pins aren't making contact, the iPhone's not sure what it's plugged into—but as long as the two or three pins carrying the power supply make contact, it will still charge correctly. So, in short, just clean it a little. It wasn't too bad."
- "It is likely the error is caused by a shorted circuit in the dock connector. I have sourced a replacement dock connector and a company that will do the replacement."
Update, a few days later: the problem seems to have fixed itself. Perhaps whatever condensate had accumulated, has passed.