In my special partition setup I have moved around/re-sized some partitions. C, primary, active, DOS D, logical, XP E, logical, Vista Installed in the order as above. XP and vista booting from C, both bootloader got installed there. XP has as root directory D:. Vista swapped the E: and C: that the root became C: and DOS gets E: (only when Vista is booted)... Everything worked fine. Now after re-sizing the partitions, the drive letter swapping under Vista does not happen and nothing runs properly after booting Vista!?!?! Maybe I made the mistake and have run Disk Director with a booted XP. What does happened? I do not understand this drive letter swapping under Vista. XP does not do/need this.