I thought I remember seeing the fix for this as going in your WTF folder and under your character there should be a layout-cache.txt file. Find the reference to xloot and remove it and save it.
Thank you for your wonderful memory! Removing the XLoot info from my layout-cache worked. A few other things went a wry but a Mazzlegasm cured that. Thanks!
I didn't have anything in layout-cache.txt -- however removing the .LUA and .LUA.BAK files from my saved variables folder and rebuilding those seems to have corrected it as well.