My pen drive is always denoted by D Drive on my laptop (with other Win partitions as E and F. But in my office room desktop, it is at times accessible as Drive I at others it is J. Win partitions are of course C,D,E and F, G and H are CD and CDRW (XP Home is in D, the pirated XP Professional over Win98 was in C that I have now deleted and modified the Boot.ini file accordingly. Thus in Word or OOO menu, the MRU from the pen drive does not work, as it shows as I while the Pen drive in explorer shows it at J, or the other way round. Why is it so, and how does Windows assign the drive letter for the removable disk. Also, is it necessary to click the tray icon of USB drive and select safely remove the USB, and why?