I'm not sure this could fix your issue. But i use below options on linux and
can download %90 of web sites.

httrack -w -r400 -q -c8 -%I --footer Firefox -#L199999 --timeout=3 --retries=2
--generate-errors -N104 -n -%H -%v -b1 --max-time=99000 --keep-alive -F
"Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101
Firefox/78.0" --robots=0