I have a 2.5" Seagate Momentus XT (500GB) in an external housing (http://www.mukii.com.tw/en/products/transimp/tip-230su-bk.html) that connects to a Toshiba Satellite Pro S750 via eSATA. It uses both an eSATA cable and dual USB cables (the enclosure doesn't power up without the USB connected). The laptop runs Windows 7 Pro 64 bit.
I discovered smartmontools today when I was trying to troubleshoot what seemed like an extraordinarily warm enclosure. I used the one that installs with Cycgwin. Also for the first time today, I could not click on the USB symbol in the notification area and eject the HD. It said that it was busy.
It's quite a coincidence that this happened for the first time shortly after I used smartctl for the first time. So I was wondering if anyone else using smartmontools on Windows ran into such coincidences. I realize that being unable to disconnect USB devices in Windows is not uncommon, but it is for me with this HD on this laptop. So I was curious as to whether there is a correlation.