The Oblivion Walker achievement is the second last one I have to check off, and the Master achievement. I have completed all the Daedric Artifacts quests, only to not have the achievement unlock!! I have the items:-
The Black Star
Dawnbreaker
Ebony Blade
Ebony Mail
Mace of Molag Bal
Masque of Clavicus Vile
Mehrune's Razor
Oghma Infinium
Sanguine's Rose
Skull of Corruption
Spellbreaker
Savior's Hide
Ring of Namira
Wabbajack
Volendrung
This is infinitely frustrating, as this was the most difficult achievement on my second play through I had to unlock!! Also, I am loathe to start a new file and attempt this achievement again without knowing if the same issue will occur again!!!
Does anyone have any suggestions that could help? Other than these two final achievements I have completed all others, including all DLC achievements, and this has really left a sour taste in my mouth after completing nearly 300 hours of a fantastic game!!!