I've successfully used GuildBank in the past, but I can't seem to get it to work now. I deleted the previous version, loaded the latest one, started WoW, opened my character/bank/skills/reputation/etc., then logged out. (I tried both /quit and /logout; no difference.) No output file was produced. (I'm looking in <wow folder>\WTF\Account\<name>\SavedVariables.)
I'm running WinXP SP2 and am not using the auto-uploader.
edit: And obviously I made sure the addon was loaded in the character selection screen.