Russell, 1. Check that your BIOS allows either booting or USB priority. 2. If these are plugged into the front ports, try using the direct off motherboard rear ones. 3. If they are connected via an external USB hub, ditch the hub. 4. Delete the USB S-ata devices from installed hardware devices (Windows button + Pause Break) 5. Re-insert USB drives so Windows Management can re-install Device ID's etc, then open up Disk Management (right click My Computer\Manage\Disk Manager) and physically remove the assigned drive letter, re-assign the drive letters (this way it becomes embedded in registry and each drive should always get the same drive letter). If none of these work, suggest throwing PC against the wall and use some threatening and violent language or less fulfilling buy a new computer :) Colin -- cdb, colin@btech-online.co.uk on 15/09/2008 Web presence: www.btech-online.co.uk Hosted by: www.1and1.co.uk/?k_id=7988359 -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist