I had this problem weeks ago, and now I have to complete the quest. After Ulfric gives his speech and enters Solitude, I try to follow but crash to desktop (CTD) during the loading screen. Here is what I have tried
I completely uninstalled all mods. Didn't work.
I completely uninstalled Skyrim, backed up my saves, reinstalled. Didn't work.
I went back about 4 levels in saves, expedited all of the Civil War quests up to this point. Didn't work.
I used console command "coc (solitude cells)"
I used console command "player.moveto (Solitude NPCs)" - All of the NPCs I teleport to are in zones/cells within solitude. When I try to enter the streets of Solitude, it crashes. Didn't work.
I turned my graphics on low. Didn't work.
I also tried:
SetObjectiveCompleted CWSiege Obj
For the stages I tried:
1 I am to join Ulfric Stormcloak in the final attack on Solitude, putting an end to the Imperial Legion in Skyrim, once and for all.
1000 (Objective is assigned): Get your Orders from
1005 (Objective is assigned): Break through the Enemy Barricade
1015 (Objective is assigned): Follow
1020 (Objective is assigned): Open the Exterior Gate
1030 (Objective is assigned): Open the Drawbridge
1050 (Objective is assigned): Enter
I set all of the above to 1 and then used "SetStage CWSiegeObj 1" and tried entering Solitude. Didn't work.
When I use player.sqs CWSiegeObj it doesn't show the stages as above though. It just shows 1, 8899, and like 9000 or some number in the 9000s.
I'm running out of ideas and it's really frustrating. Please help.