What is the Simplest way to Fix iPhone Error Codes 4013?

Maybe need new battery. Consult Apple.

Check out this tutorial: http://www.leawo.org/tutorial/how-to-fix-itunes-error-4013-1361.html

Ponder it for an hour or two, then make yourself a bowl of ice cream. Works for me.

Probably something went wrong, and your iPhone itself sees that too. That's why your iPhone asks to connect it to your PC or Mac with iTunes installed.
-Start iTunes on your PC or Mac
-Connect your iPhone to the PC or Mac
-Probably iTunes will advise to recover your iPhone.
>>If you didn't make regular backups of your data you probably will lose the data that's on your iPhone.<<
-Wait until the recovery procedure is done and see if your iPhone works again.

What if iTunes doesn't recognize your iPhone anymore in iTunes?
Thy a "soft reset' by pressing the ON/OFF button on top of your iPhone and the round menu button underneath your screen simultaneously until your iPhone reboots. Check if your iPhone connects to iTunes and try the recovery.
I hope this will help you solving your problem.

You have a situation where your phone needs to be recovered by plugging it into the computer where you sync it to iTunes. When you do this a prompt will come up on your computer that you have connected to an unidentified iPhone. It will ask you if you want to restore it from your last backup, or initialize it as a new iPhone. I recommend that you restore to the last backup, so you don't have to go to the iTunes and App Store to reinstall all your apps. The bad news is that if you have never backed up to a computer, your journey to recover your digital life is going to be difficult.

Find your solution from the list,
Apple Iphone Smartphone
Codes:

• Unlock Code,
• Password,
• Puk Code,
• Lock Code,
• Other Codes.

Software & Hardware Problems

• Software Problems (Hang, Youtube etc.)
• Hardware Problems (Display, Charging etc.)

Find Solutions for other Apple Products:
Apple Iphone 3G
Apple iPod Touch Digital Media Player

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