I installed ATI Home to test functions and decided to also test ATI Corporate as there are few more features in the corporate edition. Upon uninstalling ATI, I performed a reboot and discovered that two drive letters had changed. I have found that to change it back I have to change the drive letter on one drive at time, reboot, then change the other and reboot. I use the disk management utility in WinXP. So, I got things back to normal and then installed ATI Corporate Workstation and the same problem occurred upon reboot. I have 5 disk drives, a CDROM and DVD-RW. Two of the disk drives are SCSI. Two other drives are SATA drives that I have striped into a single logical volume using the spanning utility built in to WinXP. The fifth drive is an external drive attached to a PCI SATA controller. My normal drive letter assignements are: C: drive is SCSI 1 D: drive is SCSI 2 E: drive is spanned logical drive of the two SATA drives Q: drive is the external disk (used to store backups only) F: drive is DVD G: drive is CDROM When the involuntary renaming occurs, the CDROM becomes E and spanned SATA drives become G. I cannot find why this occurring, but it is related to the installation / uninstallation of ATI. I am concerned that this re-assignment of drive letters can affect the integrity of backups of my images or the ability to perform a restore of the image(s). Anyone seen this problem? Anyone with multiple drives want to give this a try ... uninstall the product and re-install. Steve B.