Skyrim blood on the Ice
There are a few possibilities here, according to the uesp entry on the quest
The trigger may take some time as you'll have to wait for the woman to be murdered. I came across the scene in the daytime while passing through the area; I did not wait in the graveyard (that may cause the murder not to trigger).
You can also try to trigger the quest by purchasing the house from Jorleif during the storm cloak rebellion questline.
However, it is known (see the glitches section in the entry) that the quest is bugged and may not start at all, not even via the console. In this case, then you are out of luck.
Make sure you meet the requirements needed to start the Blood on the Ice quest
- This quest is triggered by a counter that starts at the beginning of the game, which will increase each time you visit the city of Windhelm or the immediate surrounding area.
- When it reaches four, the Blood on the Ice quest will be available, although two more conditions must be met
You can always check whether or not you have met the requirements for the quest to start.
- As the lock to Hjerim will change from a "key required"-lock to a standard lock when the quest becomes available.
Official Patch Fixes
- Killing Viola before or after Blood on the Ice no longer blocks progression.
- Fixed issue where Calixto would fail to die properly in Blood on the Ice.
- Fixed numerous issues with Blood on the Ice not triggering properly
- In Blood on the Ice, Calixto can now be killed if the player owns a house in Windhelm
Unofficial Skyrim Patch changes
- Blood on the Ice will now allow you to complete the quest after the Imperials have taken over Windhelm. The guard acting as a CSI will switch properly to an Imperial as needed.
- In "Blood on the Ice" (MS11), the player's chest in Hjerim would not enable unless Wuunferth was arrested for the crime.
- Viola and Arivanya are both required NPCs for "Blood on the Ice" (MS11) but were not correctly added to the pre-quest that holds their essential aliases. If they die, MS11 will not start. If they are dead and MS11 has not yet started, they will be retroactively resurrected.
- In MS11, the objective "Get Assistance from Jorleif" is never cleared during the quest.MS11 was never counted toward the "Sideways" Steam achievement.
- If Tova Shatter-Shield is dead (actually just disabled, but that's another story) because you completed "Mourning Never Comes" (DB03) before MS11, a substitute key for Hjerim will be made available by the USKP.
- If the player chooses not to sell the amulet to Claxito during MS11, they will have it identified when Wuunferth realizes what it is.
- If MS11 has already passed the stage where it could be identified, and the player is still carrying around the Strange Amulet, it will be swapped out for the Necromancer's Amulet they should have received.
- MS11 would fail to start if the corpse cleanup code had purged the dead body in the Hall of the Dead in Windhelm. A new replacement body is generated to correct this and make the body's alias optional so that the quest will start.
- MS11SecretDoorActivatorScript has been fixed to keep it from trying to run Blood on the Ice content when that quest is not running.
- The Strange Amulet (D2328) will no longer remain an undroppable quest item when the Blood on the Ice quest is completed.