Can't update ios to 8.0.2

Question

Hello,
I want to update my iPhone 5s from 7.0.2 to 8.0.2 but when I try to do this from the phone, it says that time left for downloading is 72 hours
also was trying to update from iTunes on PC, but it stop when "connection to the software update server"
also so was trying to download ios 8.0.2 by link ******
but speed of downloading is 0-5 kb/s
Please tell me how can I update my iPhone
Thanks
<edited by host>

Answer 1

Did you check your security software settings?
Errors related to third-party security software
Error 2, 4 (or -4), 6, 40, 1000, 9006
Follow Troubleshooting security software. Often, uninstalling third-party security software will resolve these errors.
There may be third-party software that modifies your default packet size in Windows by inserting a TcpWindowSize entry into your registry. Your default packet size being set incorrectly can cause these errors. Contact the manufacturer of the software that installed the packet size modification for assistance or follow this article by Microsoft: How to reset Internet Protocol (TCP/IP).
Verify that access to ports 80 and 443 are allowed on your network.
Verify that communication to albert.apple.com or photos.apple.com is not blocked by a firewall, or other Internet security setting.
Discard the .ipsw file, open iTunes and attempt to download the update again. See the steps underAdvanced Steps > Rename, move, or delete the iOS software file (.ipsw) below for file locations.
Restore your device while connected to a different network.
Restore using a different computer.
copied from Update and restore error messages on iPhone and iPod touch