Help please; I just registered, but can't start the game

[Tiberius_Invictus]

I'm registered and logged in, but when I click the play button, I get a pop-up saying "Do you want to open or save autohaven (1.11 KB) from havenandhearth.com?"

If I open it, it asks me which program to open it with, but none start the game.

[Saxony4]

did you try to save/keep it instead of opening it?

[Galthon]

And do you have Java installed? See Borka's Java post up above, it sounds like your computer doesn't know how to open a JNLP file.
Better yet, grab Ender's client. I've tried using the official one a few times for kicks, and it was about as enjoyable as cone cow suppository.

[Tiberius_Invictus]

Thanks Galthon, that did the trick.

[borka]

I'm registered and logged in, but when I click the play button, I get a pop-up saying "Do you want to open or save autohaven (1.11 KB) from havenandhearth.com?"

If I open it, it asks me which program to open it with, but none start the game.

Open with "Java Web Start Launcher"