I believe I have the same problem.

The installation wizard process dies at varying stages (the current dialog
simply closes) and WinHTTrack is not installed, or only partially installed.

I have tried installing 3.42-2 on three separate PCs (Dell D640 laptop, Dell
GX280, and a no-name clone.

All three PCs have sufficient disk space.  The no-name clone had a fresh
install of Windows XP and nothing else installed.  The Dell PCs did have virus
protection running, but turning it off did not matter.  All three PCs are
behind a firewall and use a proxy server.

I have searched the forum and do not see any related comments.

Is there any prerequisite software requirements?