Updating to IOS 5 - "Device isn't eligible for the requested build." SOLUTION

Question

After two days of struggling to update to IOS 5. Here is how I made it work...
I continuously got this error message:
Here is how I was able to get past this roadblock & update my iPhone4 & iPad2 from 4.3.5 to 5.0. Be sure your iTunes is up-to-date 10.5 (141)
Step 1:
The hosts file may also be blocking the iTunes Store.
Open the Terminal utility located in Applications > Utilities.
When Terminal opens, open the hosts file by typing entering the following command and pressing Enter:
sudo nano /private/etc/hosts
Type your user password when prompted.
Note: This requires a non-blank admin password.
Edit the hosts file:
The hosts file contains some comments (lines starting with the # symbol), as well as some default hostname mappings (e.g. 127.0.0.1 – localhost).
You can navigate the file using the arrow keys.
If an entry is found containing apple.com, add # and a space to the beginning of that line.
Note: If this is a work system, the hosts file may be used to redirect to local resources, such as software updates. Consult your support resources.
Save the hosts file.
When done editing the hosts file, press Control-o to save the file.
Press Enter on the filename prompt, and Control-x to exit the editor.
Step 2:
Restart computer
Step 3:
Once computer has rebooted, with iTunes closed, put iPhone into Recovery Mode. Here's how:
                         Step 1.
                         Disconnect and Switch off your iPhone if it is connected to your Mac. Also make sure to close iTunes.
                         Step 2.
                         Press and Hold the Home button on your iPhone.
                         Step 3.
                         While still holding the Home button, connect the USB cord to your iPhone. Launch iTunes if it didn’t launch already.
                         Step 4.
                         Do not let go off the Home button until you see a pop up saying that iTunes has found an iPhone in Recovery mode.
Once I successfully got to this point, I was able to update my iPhone4 & iPad2 to IOS 5.
Hope that helps.

Answer 1

I'm sorry, but Apple does not provide a downgrade path for iOS. Because downgrading is unsupported by Apple we cannot discuss it on these forums.
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