I've done the first parts of the Harper quest, Jaheira left the party and then came back and told me to go to the Harper place.

When I get there the door is locked and cannot be opened by any means.

I tried to teleport inside with cheats but the war party inside just stand there and I can't engage in conversation with Galvarey or any of them.

What to do?

Is there any console command to open doors or to reset quests?

* What version of the game are you using?
* Do you have any mods installed?
* Did you wait too long before going back to the Harper building?

There are two versions on GOG: original BG2 and BG2:EE. Wait. You are saying that Jaheira left your party after 'rescuing' Montaron? That is early on in Jaheira's Harper Pin quest line, and she is not supposed to leave there (unless you deliberately delayed the Xzar/Montaron angle). She is supposed to leave way later -- Jaheira's quest is a long one -- when she is summoned back to the Harper hold by Meronia after resting outside Athkatla.