The duration of the update process can range from 15 minutes to 2 hours, depending on the type of update, the amount of device data, and the number of applications on your BlackBerry device. You cannot use your device or make emergency calls when the update is in progress. Do not remove the battery while the update is in progress.
Over the wireless network
You can update your BlackBerry Device Software over the wireless network if a Wireless Update icon appears on the Home screen of your device. You can also check for updates manually through the device options. The available update might be a complete software update, or a partial software update only. If the available update is a complete software update, your device data is backed up on your device and restored during the installation process. Depending on the options that your wireless service provider or administrator sets, you might not be able to update the BlackBerry Device Software over the wireless network. Depending on your wireless service provider, extra fees might apply when you download the update to your device.
From a web site
If your email account uses the BlackBerry® Internet Service or a BlackBerry® Enterprise Server that supports this feature, you can update your BlackBerry Device Software by connecting your device to your computer and visiting the update web site at www.blackberry.com.
Using the BlackBerry Desktop Software
If you have the BlackBerry Desktop Software installed on your computer, you can update your BlackBerry Device Software from your computer. For more information about updating the BlackBerry Device Software from your computer, see the Help in the BlackBerry Desktop Software.
Research In Motion recommends that you regularly create and save a backup file on your computer, especially before you update any software. Maintaining an up-to-date backup file on your computer might allow you to recover device data if your device is lost, stolen, or corrupted by an unforeseen issue.