I have a very large D drive on my HP pc and a (relatively) small (128 gb) SSD C drive. I've had situations where there wasn't enough work space on the C drive for me to compact the folders until I tracked down the emails with large attachments and blew them away. I have every last bit of user data sitting on the D drive (docs, downloads, music, video, pics) ... except the TB email folders. And they're big enough to cause problems. Give me an option to select D as the default drive for TB email folders.