Let me make sure i understand what you are doing/trying to do. The way I understand xcopy (dusting off my dos usage) You maybe trying to copy everything from a folder called c:\nul to a folder called c:\cws. Is that right?
Try this... get back to c:\cws (or any folder really) and type:
xcopy a:\nul\*.* c:\cws\*.*
That will copy all the files from the nul folder into the cws folder. If you want a folder in cws named nul, type this from the cws folder (c:\cws)
xcopy a:\nul\*.* c:\cws\nul\*.*
I hope this helps,
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