If you want to create or generate a file of a certain size in Windows XP, Server, Vista or later versions or MS-DOS, you can use the Fsutil command . Here is the instruction:

- Log in as user name with Administrator privileges

- Open command line CMD and type in:

“fsutil file createnew <location\name of file> <size in bytes>”

For example:

fsutil file createnew d:\temp\1MBfile.txt 1000000