Q: How to change instance in ESO?
Elder Scrolls Online uses a megaserver technology, meaning all players are playing on one server. Unlike many other games like World of Warcraft where you choose servers on which you’ll be playing on.
The only choice you can make when creating your character is whether you wish to play on the American or European megaserver.
Anyway, back to your question and my point. Since there are thousands and thousands of players online at all times, players in a particular zone can still not see each other if they are in different “instances” of that particular zone.
The easiest way to change your instance is to simply try and relog into the game. In most cases you will switch instances, and if it doesn’t work on first try give it 2-3 more tries and it will. You don’t need to completely shut down the game, simply log out to character selection screen.
You can also try to teleport directly to a particular player (right-click on your friends name in social window, or name of some guild member). That will put you directly in the instance that player is in.