I changed the hard drive in my m400 and i doesnt load windows says somthing about a dianostic disc! what do I do.
Your question is a little vague, but If you do not have the original install disks, you need to go to Toshiba and download the Hard Disk Raid Driver, then copy them to a thumb drive, then load the drivers when prompted by windows. Without the original disks, it does not matter what version of Windows you install, but without the Toshiba driver for the version of windows you have, it will not recognize the hard drive.
When you mention diagnostic disk, did you try and buy the disks from someone after you bought the machine. If so they may have given you the engineering disks, and not the windows disk.
One option you do have is if you still need windows and the correct disks, is to contact Toshiba technical support. You can buy the restore disks for about $25, but they take about ten days to ship.
G-Luck. Read More At : Portege M400 PPM40U01000E Tablet PC...