Touchscreen deadspots: What to try before taking your iPhone for service

Though it's impossible to gauge how widespread the problem is, a number of users are reporting an issue where certain spots on the iPhone's MultiTouch screen -- particularly a strip about 1/2 inch in height somewhere below the top of the screen -- will not accept input. If indeed you have a defective screen, Apple is apparently willing to replace it with little hassle. However, to ensure that a more innocuous issue isn't at play, try the following first:

• Reset your iPhone Sometimes, ostensibly dead spots on the screen are merely the result of frozen applications or an unresponsive interface rather than actual hardware failure. Press and hold the Sleep/Wake button (on the top of the unit) and the Home button simultaneously for several seconds until the Apple logo appears and check for persistence of the issue.
• Clean the screen It may sound trite, but a glaze of any foreign substance can cause operational difficulties for the iPhone's screen. Clean the screen with the cleaning cloth that came in the box with the iPhone.
• Restore your iPhone As a last resort, try restoring. This can remove lingering software issues that might be causing a lack of screen response. To perform a restore, Connect your iPhone to your Mac or PC and, in iTunes, click the Restore button under the Summary tab. Restoring the phone will erase contacts, calendars, photos and other data on the phone, but will restore automatically backed-up information including text messages, notes, call history, contact favorites, sound settings, widget settings, etc.

If you're still having problems, contact Apple for repair.

Also, if you are indeed experiencing a hardware failure, please drop us a line indicating what version of screen your iPhone uses. To discover this information, put your iPhone in field test mode by accessing the Phone application, tapping Keypad, then entering *3001#12345#* and pressing Call. Tap Versions, then inspect the entry next to LCD Panel ID. Let us know whether your iPhone is a 7 series or 5 series