Error 1611 C an be Fixed when Restoring (Downgrade) iPhone 4/3GS from iOS 4.3.5 to iOS 4.3.3 iPad, iPod Touch 4G/3G . Actually, this Error 1611 is one of the Common Errors, that are faced by Users when Restoring their iPhone 4/3GS, iPad, iPod Touch 4G/3G.
When you get error 1611, iTunes shows this message “The iPhone “your device name” could not be restored. An unknown error has occurred (error 1611)”.
How to Fix 1611 Error iPhone 4/3GS, iPod Touch and iPad 2/1 after Restore iOS 4.3.5 to 4.3.3:
Here you can have to Different Methods on How to Fix 1611 Error
Method One – Reboot your Computer and Change the USB Port
Method 2 – Unable to Fix 1611 Error while Restoring your iOS Device from iOS 4.3.5 to 4.3.3, then please Watch this Video on How to Fix Error 1611 in iTunes. Via