Here's my advice
1# Turn off autosave
2# Never overwrite a save file
This will not only improve stability in the long term, (but you'll always have a long list of backup saves until you manually delete them).
3# Double check your inventory you might have picked it up in your zeal and not realized it.
Thanks auto-save has been turned off for months as it helped prevent crashing.
ermm yeah i always overwrite saves, it keeps down on the confusion lol.
I did not pick it up.
Thanks though

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I just thought of something near where the armour should have been there was a false wall where i could fall down and then it would crash. I'm wondering if i pushed it down there by accident.