The default is for XP to assign the C logical drive letter to the logical partition Windows is installed on. If you still have the original Toshiba software installation on this computer, your physical hard drive inide the laptop has two logical partitions - C is the first partition (logical drive) on the laptop's hard drive, and the hard drive also has a second partition that may or may not be visible to you the user, called the Recovery partition or similar - if it is visible to you it is probably the D logical partition.
XP by default assigns logical drive letters in the order in which the drives were detected by Setup originally according to certain rues, then after that any logical drives added use letters higher that the highest drive letter already used.
In your case, C and D are probably partitions on the hard drive, if the second partition on the hard drive is visible to you, and E is probably your CD or DVD drive.
When you add an external hard drive, it's logical drive letter will by default be F or higher.
If the second partition on the hard drive is NOT visible to you, you see only the C partition on the hard drive, and D is your CD or DVD drive.
When you add an external hard drive, it's logical drive letter will by default be E or higher.
Simlarly, if you no longer have the original Toshiba software installation on the computer, as in you installed XP from a regular XP CD, and if there is only one partition on the hard drive inside the computer, by default you see only the C partition on the hard drive, and D is your CD or DVD drive.
When you add an external hard drive, it's logical drive letter will by default be E or higher.
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When you drag files from one place to another in Windows, they are "moved" in three steps - the files are copied from the source, pasted to the destination, then the original files are deleted.
Some really huge files such as full length movies cannot be dragged and dropped - they must be Copied, Pasted, then Deleted
, but if that were the case you should get an error message.
If you interrupted the process before the original files were deleted, they should still be there at the source.
If you interrupted the process AFTER the original files were deleted, the source files MIGHT be in your Recycle bin.
If you haven't already done so, unplug the external hard drive, after clicking on the icon in your taskbar that allows you to safely disconnect it after clicking on a thing or two - whatever damage has been done has already been done.
Then reboot the computer, and look around.
There may be something wrong with the hard drive in the computer, either in the Windows software only, or the hard drive itself is defective.
To rule out a defective hard drive, check your hard drive with the manufacturer's diagnostics.
See the latter part of response 1 in this:
http://www.computing.net/windows95/...
If you don't have a floppy drive, you can get a CD image diagnostic utility from most hard drive manufacturer's web sites, but obviously you would need to make a burned CD, preferably a CD-R for best compatibilty, on another computer if you need to.