The basics

If your iPhone acts up in a general way—won’t turn on, won’t appear in iTunes, or quits and locks up—try these techniques.

No iPhone startup

Is your phone just sitting there, with its cold black screen mocking you? Try charging it with the included charger rather than a USB 2.0 port. If you get no response after about 10 minutes, try another electrical outlet. Still nothing? Try a different iPhone cable.