To update any Apple product, you must have the most up to date version of Apple iTunes. Currently that version is 10.1.2. To double check your iTunes version and/or install the newest iTunes version, go to iTunes on your computer and click "Check for Updates." You can also go directly to Apple for the latest update.
NOTE: If you haven't backed up your iPad, it might be wise to do it before installing the new iOS 4.3.
After you have updated iTunes to the most recent version, follow the instructions below to update your iPad to iOS 4.3.
Normal Update Procedures:
1) Open iTunes
2) Connect your iPad to you computer
3) Select your iPad in the Source List.
4) Click "Check for Updates" on the right hand panel.
5) A pop up box will appear. Click "Download and Update"
6) Follow the instructions on the screen.
7) Updating takes anywhere from 10-45 minutes depending on your download speed. The file size for iOS 4.3 is just under 600 mega bytes.
For PC users: If you are having trouble downloading and installing the operating system on your iPad, many times that is due to your computer's anti-virus or firewall software. Disable your anti-virus and firewall software and restart iTunes before trying to update your iPad again.
Manually updating your iPad
I generally love Apple products but the most annoying thing as a techie is the limitations one has in using and customizing the Apple OS. For some strange reason I can never update my iPad normally simply going through iTunes. I get an error right at the end of the download. I even shut down my firewall and anti-virus software and still the problem exists. The glitch I always get is at the end of the file when I have update 596.9MB of 596.9MB, I get an error message stat err=-3259. I know it's not my internet connection since I have a fiber optics internet connection at home, and every download I ever do goes just fine. So for those of you frustrated with Apple's update through iTunes, here is a tutorial on manually installing the software yourself.
1) Download the iOS 4.3 IPSW file you're the iPad. The direct download link from Apple is here.
2) Open iTunes on your computer and connect your iPad using the USB cable.
3) Depending on whether you run Windows or have a MAC, follow.
a. Mac - Hold the Option key and then click on the "Check for Update/Update" button.
b. Windows PC - Hold the Shift key and then click on the "Check for Update/Update" button.
4) A Dialog screen will appear prompting you for the location of the IPSW file you downloaded. Find the file in the file browser and select the IPSW file.
5) iTunes will now use the iPSW file and update your iPad to iOS 4.3. This will take approximately 10 minutes.
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