TL;DR: discard any Qualichor you have. Get a fresh one after next reset, take it to Fynch, and you'll be able to pick the quest up again and it should still have the previous progress you'd accrued on it. Bungie, This quest seems to get buggier if it's being done at the same time on multiple characters. I run all three classes. I've had the Memory Alembic quest disappear from each of my characters. This time around, before reset on 4/5, I had the Memory Alembic quest disappear from my Hunter's quest log. Before reset, I made sure I didn't have any Qualichor in my inventory. I sharded any that were in inventory or postmaster. After reset on 4/5 I acquired a Qualichor on my Hunter by doing an Investigate Dead Scorn --> Find the Lightbearer Hive --> Loot the Chest loop. After acquiring a fresh Qualichor, when I went to Fynch, he had the quest available. When I picked up the quest, it already had some progress on it. Today after reset on my characters I had: Warlock w/ Memory Alembic quest at 6 of 8 completion Hunter w/ Memory Alembic quest at 6 of 8 completion Titan without a Memory Alembic quest. Today on my Hunter, I went to the Miasma and did the Investigate Dead Scorn --> Loot the Chest loop. This got me to 7/8. Then I fast traveled to Quagmire, and a group of Lucent Hive Inquisitors was already there and being beat up on by a guardian. I finished the last of the Lightbearer Hive/Guardians, but no chest spawned. Just as I was finishing the last Ghost I thought I heard the "retreat" scream and since I didn't see the "chest appeared" flash I figured "Okay, maybe the timer fizzled just as I was finishing off the squad." I went to Florescent Canal, patrolled around until ANOTHER set of Lucent Hive Inquisitors --> Lightbearer Hive/Guardians spawned. We killed them off, I opened the chest and [b]saw a qualichor drop[/b] so I then tried to find the Deepsight Hidden chest and open it with the Refined Qualichor. I got to the chest, and saw "[b][i][u]Requires Refined Qualichor[/b][/i][/u]". I checked my quest log, and THE QUEST HAS DISAPPEARED AGAIN. So now I've used my once-a-day Investigate Dead Scorn --> Loot the Chest loop on my Hunter. This means I can't do THAT loop on my Warlock. What's worse is that I won't be able to recover the quest on my Hunter until next reset. So. Damn. Frustrating. 4/10 Update: On my Warlock, I had the Memory Alembic quest fizzle out today. The quest progress was at 7 of 8. This would have got me a Refined Qualichor and let me open up the secret chest after a Hive Inquisitor event. Details in hopes it helps with troubleshooting: I went to The Miasma to do a once-a-day Investigate Dead Scorn --> Loot the Chest loop on my Warlock. As soon as I investigated the Dead Scorn, I heard the starting sound for the "Lucent Hive Inquisitors in your sector" event. So I had "On The Trail" active. Instead of chasing down the executioners hoard chest, I stayed in the area so I could finish the Memory Alembic quest. I killed the Inquisitors, opened the chest, saw the qualichor drop. I went to the hidden chest and... "[b][i][u]Requires Refined Qualichor[/b][/i][/u]". Nope, no Refined Qualichor to use at the hidden chest. What is this, Bungie?