checking for csc.exe... no configure: error: You need to install either mono or .Net ankur@ubuntu:~/gtk-sharp$ whereis mcs mcs: /usr/bin/mcs /usr/X11R6/bin/mcs /usr/bin/X11/mcs /usr/share/man/man1/mcs.1.gz ankur@ubuntu:~/gtk-sharp$ mcs -version error CS2007: Unrecognized command-line option: `-version' Compilation failed: 1 error(s), 0 warnings ankur@ubuntu:~/gtk-sharp$ mcs --version Mono C# compiler version 1.1.17.1 ankur@ubuntu:~/gtk-sharp$ echo $PATH /usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/bin/X11:/usr/games:/usr/bin/mono:/usr/bin