|OK so it's got a windows directory full of files so we can assume it wasn't reformatted before you got it and is supposed to be working.|
What did it say when you typed dir c:\windows\himem.sys? That will tell us if the file is actually there.
Model # and amount of ram?
What did the seller tell you about the laptop's working condition?
In addition, type type c:\config.sys and enter. Post back what it says.
And type type c:\autoexec.bat and enter. Post back what it says.
That's 5 different questions.