> I tried to copy Wikihow.com but HTTRACK failed to
> copy.Can i copy Wikihow.If it is possible then
> Please tell me How.

Don't tell us what you tried, what you got, what you didn't get, what version,
what settings or what the log says. Don't expect any answers - we're not mind
readers.

Robots.txt contains:
User-agent: HTTrack
Disallow: /

So you're going to have to override that setting.