Windows 7: WLM 2011 Ques

When I was using XP and OE sometimes I would get a popup box in OE saying to free up disk space email messages would be compacted and sent to the Recycle Bin. I got a popup box the other day when I opened WLM but it happened so fast I couldn't see what it was doing.
Does WLM do the same thing when the storage folders get full and where do the messages go to?

I'm pretty sure that it doesn't/didn't say anything about the recycle bin since "compacting" is not the same as "deleting". In general, you can always say "yes" to the pop-up without fear of loosing anything.