Some of the causes of iTunes 1671 error may be due to:
Step 1 :
Disable antivirus programs on your computer or Mac.
Step 2 :
Start your iOS device.
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Press and hold the on button, turn off the power for about 10 seconds.
Step 3 :
Connect your iOS device to your computer with a USB cable , then open iTunes and try updating iTunes again.
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Step 1 :
Disable antivirus programs on your computer or Mac.
Step 2 :
Next you need to find the Host file on the computer.
Step 3 :
On a Windows computer:
On a Windows computer, visit My Computer => Drive C: /.
Next step, access by path:
Windows => System 32 => drivers => etc and search for Hosts file .
Drag and drop Hosts file to Desktop screen.
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On Mac:
You will have to use the Finder to search the Hosts file, then drag and drop the Hosts file to the Desktop. On the Menu Finders bar, you access Go => Go To Folder .
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Step 4 :
On the next frame, enter the location of the path below and press Enter:
/ private / etc / hosts
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Step 5 :
A Finder and file host window will appear on the screen here. Drag and drop the file to the Desktop screen.
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Step 6 :
Mine iTunes on your computer and try restoring your device. After the process has finished, you can "bring" the host file back to the location in the directory.
Good luck!