How to Fix Error 1603 iTunes



When trying to restore your iPhone in iTunes, you may see the following error message:

The iPhone could not be restored. An unknown error occurred. Error 1603


Here are several troubleshooting steps that may resolve this issue.

Update iTunes and iPhone

To update iTunes:

  • Windows: Choose Help > Check for Updates.
  • Mac: Choose iTunes > Check for Updates.

See this document for steps to update iPhone.

Restart Your Computer

Simply restarting your Mac or Windows PC may allow you to successfully restore your iPhone.

Try a Different USB Port

Connect iPhone to a different USB port on your Mac or Windows PC. USB 2.0 ports that are built-in to the computer are preferred. After doing this, attempt to restore your iPhone in iTunes.

Restart Apple Mobile Device Service (Windows only)

Restarting the Apple Mobile Device service on Windows XP or Windows Vista may allow you to successfully restore iPhone. Refer to the steps below for your version of Windows. Note: You’ll need to sign in with an administrator account for these steps.

  • Windows XP
    1. Close iTunes and disconnect iPhone.
    2. Choose Start > Control Panel.
    3. Inside the Control Panel, open Administrative Tools.
    4. Open Services.
    5. Select Apple Mobile Device and click Stop the service as shown below:

After the service is stopped, click Start the service.

After the Apple Mobile Device service has started again, open iTunes and connect iPhone.

Select iPhone in the Source list, click the Summary tab, and then click Restore.

Reset the iPhone sync history and restore

To reset your Sync History:


  1. Open iTunes
  2. On the Edit menu, click Preferences.
  3. Click the iPhone tab.
  4. Click the Reset Sync History button.


  1. Open iSync.
  2. Choose iSync > Preferences.
  3. Click the Reset Sync History button.

After resetting sync history, restore iPhone.

Create a new user account and restore

Create a new user account and then restore iPhone.

Use the steps below if you’re not sure how to create a new user. After creating the new user, log in to that account, open iTunes, and determine whether the issue you were experiencing persists in this new user.

Windows Vista and Windows XP

  1. From the Start menu, choose Control Panel.
  2. Open User Accounts.
  3. Select Create a new account and follow the instructions to complete the account setup process.
  4. Once the new account is created, choose Log Off from the Start menu.
  5. Log in to the newly created user account.

Mac OS X

  1. Choose Apple menu > System Preferences.
  2. Choose View > Accounts.
  3. Click the “+” (you may need to authenticate to be able to click this).
  4. Give the new user a name and short name and enter a password.
  5. Select the checkbox for “Allow user to administer this computer”. This makes the user an administrator user.
  6. Click Create Account.

Looking for something?

Use the form below to search the site:

Still not finding what you're looking for? Drop a comment on a post or contact us so we can take care of it!