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Mac OS X
1. On your Mac, open your Applications folder.
2. Navigate to the Utilities folder.
3. Open Terminal.
4. Type sudo nano /etc/hosts (without quotes) and press enter.
5. Enter your password
6. Use the down arrow key to find the gs.apple.com entries. Once the cursor is in front, make sure you comment out the line(s) by entering # in front of the text.
7. Save the file by pressing CONTROL+O.
8. Exit the nano editor by pressing CONTROL+X.
9. Restore your iDevice.
Windows
1. Press Start, then Programs, then Accessories
2. Launch Notepad or WordPad
3. Click Open from File menu.
4. Browse to Windows/System32/drivers/etc
5. In files of type: select all documents
6. Open hosts
7. Delete all line that have gs.apple.com or similar
8. Hit Save
9. Restore your device
You should now be sorted and up and running! Please feel free to share your experiences in the comments section below.