I have a Lumia 1020 (along with a 635 and 920) on AT&T. With 8.1 (DP), running Black and Cyan, I had no problem using Internet Sharing. Once I upgraded to 8.1, update one, Internet Sharing would not work, with Black or Cyan (did multiple fresh installs). Have no problems with 635 or 920 and update 1 (have not tried Cyan on 920). Others of you may have the same problem. I found a workaround.
On my 1020, the Internet Sharing will toggle on but the computers cannot connect (W 8.1) to the phone. However, if I manually add the network as non-broadcasted, the computer will connect and Internet Sharing works. On your 1020, toggle Internet Sharing on. On your Windows computer go Network and Sharing Center > Set up a new connection or network > Manually connect to a wireless network > then type in your network name (the one listed in Internet Sharing on your phone), WPA2 Personal, and the password (the one listed in Internet Sharing on your phone). Your computer should now connect. I assume this would work on a Mac as well.
If you are having problems, I hope this helps.
On my 1020, the Internet Sharing will toggle on but the computers cannot connect (W 8.1) to the phone. However, if I manually add the network as non-broadcasted, the computer will connect and Internet Sharing works. On your 1020, toggle Internet Sharing on. On your Windows computer go Network and Sharing Center > Set up a new connection or network > Manually connect to a wireless network > then type in your network name (the one listed in Internet Sharing on your phone), WPA2 Personal, and the password (the one listed in Internet Sharing on your phone). Your computer should now connect. I assume this would work on a Mac as well.
If you are having problems, I hope this helps.
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