Why tidy doesn't write output file?

The first line doesn't output ~index.html, but the second does output 
~tom's Home.htm.

Does anybody know what's wrong?

  tidy -config default.tidy -o "C:\Web\site one\~index.html"
"C:\Web\site one\index.html"


tidy -config default.tidy -o "C:\Documents and Settings\TS\My 
Documents\~tom's Home.htm" "C:\Documents and Settings\TS\My 
Documents\tom's Home.htm"