Hmm, my system is 'stable' - as you put it - and it didn't for me. And the issue, as far as I can see, which was clear fr om the subject line of this thread, was that it was a potential security issue. I'd have to agree if your are in an environment wh ere these things are a consideration. If the contents of cached emails are in readable form and are not cleared, then I can see how this might be an unwanted or unhelpful 'feature' and 'infuriate' someone enough to post an emotive criticism of The Bat!. Perhaps a specific user option should be added to TB! to either clear or not to clear the TB! cache on exit. Not that affects me now because I'm back on v4. The v4 cache folder stores images only from what I can gather. I regularly manually clear that as well as it tends to grow and grow. Although it isn't a problem as far as security is concerned because it's just images. And my mail base is on a TrueCrypt drive. Perhaps if 'xelusi' is worried about security he should install the excellent TrueCrypt software, which is free, and create a secure container for his email. No need to wipe anything then, and no security issues.