Fatal:Unable to execute command: /usr/bin/perl.exe

As part of trying to build OpenSSL using Cygwin on Windows XP
As per the install file of the OpenSSL distribution:

To build OpenSSL using Cygwin:

* Install Cygwin (see http://cygwin.com/)

* Install Perl and ensure it is in the path. Both Cygwin perl
(5.6.1-2 or newer) and ActivePerl work.
...............

So I have downloaded ActivePerl (the msi file) and install it using the default location C:\Perl which was wrong.

Solution: install ActivePerl in C:\usr\ if you want to get rid of the problem.