Dawnguard quest wont start

[Skipper]

I bought Skyrim legendary edition in retail, Until now dragonborn and hearthfire worked correctly, but Dawnguard never started. I have defeated Alduin. I have killed Miraak. I became the Listener. I am thane in almost every hold. I am the Arch-Mage of the college of Winterhold. And the Thieves Guild Master as well. I got married. I adopted two childs, and built a home. By now, I'm level 44 and no guard told me a word about the dawnguard. Anyone know how to fix this?

[gnewna]

Hmm, is it possible the Dawnguard.esm file isn't activated for some reason? Is there any evidence of Dawnguard content in-game, e.g. if you come across vampires in the world, are they still in ordinary black robes, or do most of them have the snazzy vampire armour (looks a bit like bike leathers)?

[Wray of Sunshine]

Firstly, check that the DLC in actually installed by looking under the main menu. Steam should automaticly download this kind of stuff, but you may need to mannuly install it by syncing it with the Steam Cloud.

If it is installed, check the two new locations. At the very North-West of the map will be the Vampire Castle that will appear on your map when you get close enough (You won't have access to it yet). If you see a castle icon and it's called something along the lines of "Volkiher" then it has succesfully installed. Alternatviley, at the very opposite of the map there will be the Dawnguard castle, which will be hidden away in a secret valley. The icon should apper on your map when you travel to the nearest village. If neither of these are visible, then Steam has screwed up... Remember, sync to Steam Cloud.

If it is there, you may want to try other methods of starting it rather than waiting for it to come to you. Go to taverns and ask about "rumours". Also try using the wait option for about 48 hours, and an Orc may come up to you and offer a place in the Dawnguard. At this point, you proabaly want to contant Steam dircetly, but there is a few more things you can try.
If you go the Skyrim Wiki, you can find the quest page. Find the ID, open the console and manually start the quest from there by following the instructions under the ID. This will proabaly work, but only for a last resort. This may cause game-breaking bugs later on down the line.

Remember, try to contant Steam directly if all of the above fail