"wpchost.exe has stopped working"

When you run Web Proxy Checker Pro under non-administrative account you may get the error "wpchost.exe has stopped working" (see screenshot below).

That happens because Web Proxy Checker Pro process (wpcp.exe) does not have rights to launch the host process (wpchost.exe).

To avoid this problem you need to change Privilege Level for wpcp.exe - see the screenshot below.