Hi Htetmyetnaing. This message often comes when the downloaded update is out of date. But 11.1.2 is still current. Have you done previous updates over this network?
Be sure the router/firewall is not blocking apple.com URLs, especially gs.apple.com.
Hi Htetmyetnaing. This message often comes when the downloaded update is out of date. But 11.1.2 is still current. Have you done previous updates over this network?
Be sure the router/firewall is not blocking apple.com URLs, especially gs.apple.com.
you need to be on wifi, to update over the air.
how to install ios 11.1.2 on my iphone 6 64Gb?