I have no idea what caused it, but I:

1. performed a full scan
2. performed a custom search, where the table was full
3. performed a new search, and bought a few items
4. pulled the items out of the mailbox and mailed them to an alt
5. relogged to said alt

Upon noticing I couldn't see the disenchant distribution, I noticed my entire WTF-file got wiped. All my historical data, searches, history and configuration gone.

Had it happen a second time now, after more or less the same actions

Happened to me as well today. All aux settings wiped!

aux 3.1.4 on WotLK

Afraid I'm unable to remember the exact sequence of events.