It looks like my chances of completing this main story line is over, and I didn't even get a shot inside. While exploring I came across the Embassy and proceeded to kill the 4 guards outside through the fence only to find out later that I need them to enter the door for the party, which is not allowed to be picked. My saves do not go back far enough to correct this so I'm attempting to Wait for the guards to respawn but I've waited at least 80 days now and am getting the feeling that they won't be coming back.

Has anyone else encountered this or has any suggestions?

Thanks,
Grummet


Update: I managed to get the guards to respawn after waiting a few months. I started the quest and as I approached the guard at the bottom of the stairs instead of being asked for my invitation I was greeted with "You! Back to inflict more pain on me?"

ARE YOU KIDDING ME??!

What happens when you start the quest and arrive at the embassy on the carriage?

Yes. What does happen? I woul expect guards to be reset for the quest.

Nothing happens which is causing the problem. The guards remain dead and are lootable, however none of them have a key to get inside. Everything else is there, the carriages and the other party member who doesn't do anything.

Try staying away from the game cell the embassy is in so it has a chance to respawn.
Every time you enter the cell, the respawn time resets.

I dont know how long it is in Skyrim, longer than the three days in Oblivion at least.
Try staying away from there for at least a week, or maybe a month.
I know for instance that only when I stayed away from the Winterhold college a while because I found a new home, the remains of the ghosts finally dissapeared.

Yes. Every location should eventually respawn enemies if left alone for a while. This should also work for the Embassy, I'd hope.

Thank you both for the tip. I'll test it out tonight and let you know if it works. When I waited the 80 days I was standing outside the Embassy >.<

Waited about 3 months in another location. The dead bodies disappeared after 30 days but nothing else after that. Started the quest again and there were no respawns. =/

Well I think it's officially broken for me. See Update in original post.

Thanks all who tried to help.

Did you try killing them again? Maybe one of them has the key this time.

I did, no luck. The only way to loot is to kill them through the gate and then start the quest. You also cannot Pickpocket them during the beginning of the quest even if they had a key. After watching a video walkthrough for the quest I believe the door just becomes unlocked when you show both guards your invitation and you are never actually given a key.

Ive tried everything I could think of, attacking the guard then disappearing before starting the quest. Waking up without clothes, using Invisibility pots before getting on the wagon to arrive there, trying to jump over the wall and get to a side door.

Maybe I'll just kill the guards again and come back when I don't have any more quests.

I had the same thing happen to me but it had to do with that Drunken quest and the wedding ring.... I killed an old lady out in the boonies and looted a wedding ring from her.... I didn't even know it was for a quest until AFTER I sniped the old hag with my bow, robbed her and went back to town. I think I had to talk to her because I can't turn in the wedding ring to complete the quest now....

Tip: "open world" shouldn't mean that you should be able to to compile an unlimited amount of quests that you can't even finish because you're trigger-happy.
Make important NPCS (like guards that are needed to let you inside of a place, or those with important quest chats) unable to be killed.