When attempting to update my iPhone I get the following error: "Cannot Update, Unknown Error (1602)." How can I update?

Many users have reported an unknown error message (1602) when attempting to update their iPhones to firmware versions 1.1.3 or 1.1.4. Though there are many documented approaches to solving this problem, none seems to work for everyone. Our readers have reported success using the following approaches:

1) Reset sync history (instructions here)
2) Turn off Auto-lock on the iPhone prior to attempting an update. There is no indication why auto-lock being on would affect the update process, however.
3) Ignore prompts to update the iPhone when it is docked/plugged in. Instead, cancel this and manually select Update from within iTunes.
4) If all else fails, throw the iPhone into restore mode and restore to the newest version of firmware.