I posted this a few months ago to the Nexus forums, but unfortunately nobody there was able to help. As I recently returned to Skyrim and found this error happening again, I thought I'd ask you lovely people as well.

Essentially, I have this recurring problem where Dawnguard quests won't progress and scenes won't happen.

On my last savegame, it happened in the Soul Cairn where Valerica wouldn't come to the barrier and talk, and when I used the console to complete Beyond Death the whole questline basically fell to bits. When I tested this on a new character, it all worked perfectly and I couldn't replicate the error.

This time, I started the Dawnguard questline before doing anything else and took no new quests while I was doing it. I got through the Soul Cairn with no problems and everything progressed normally until I got both Elder Scrolls in Seeking Disclosure, at which point the "return to Dexion" objective did not present itself.

I used the console to get the objective, but on completing it the next quest did not start.

In my Papyrus log, I get errors like this (this one was when Chasing Echoes should have started and didn't):

Error: Cannot call AddToMap() on a None object, aborting function callstack:[DLC1VQElder (03005DA9)].DLC1_QF_DLC1VQElder_01005DA9.Fragment_13() - "DLC1_QF_DLC1VQElder_01005DA9.psc" Line 59[05/10/2014 - 01:10:45PM] Error: Cannot call SetStage() on a None object, aborting function callstack:[DLC1VQElder (03005DA9)].DLC1_QF_DLC1VQElder_01005DA9.Fragment_13() - "DLC1_QF_DLC1VQElder_01005DA9.psc" Line 64[05/10/2014 - 01:10:45PM] warning: Assigning None to a non-object variable named "::temp0"stack:[DLC1VQElder (03005DA9)].DLC1_QF_DLC1VQElder_01005DA9.Fragment_13() - "DLC1_QF_DLC1VQElder_01005DA9.psc" Line 64

When it broke in the Soul Cairn I got a very similar message, saying that it couldn't run scripts on a none object (at the point where Serana should have run up and called to Valerica).

I've googled this error, and taleden on the Creation Kit website suggests the following:

However, as a scripting beginner I'm not sure how to apply this knowledge.

I'm not using any mods which should affect the Dawnguard questline, and I haven't added or removed any mods during this game. I can post my full log, load order and any other information if needed. Please could anyone give help or advice?

Thank you!

Try uninstalling the Hearthfire DLC before entering the soul cairn then re-installing after you have acquired the Scroll - appears to fix the bug.

Try that on that character:

This time, I started the Dawnguard questline before doing anything else and took no new quests while I was doing it. I got through the Soul Cairn with no problems and everything progressed normally until I got both Elder Scrolls in Seeking Disclosure, at which point the "return to Dexion" objective did not present itself.

I assume you have the unofficial patches installed. !!!