Error reading machine specific preferences - but fails to say what

Nothing like a really vague error at the start of the day.

 I am glad to see that it hasn't reverted the preferences to a factory reset - However, I would be interested in working out what specific aspect of the preferences could not be read.

A cursory look suggests I've lost some brushes that I've created recently. And recent file history (but I'm not bothered about that) But maybe more. 😞