You get this error message when you try to install the 64 bit version of GAMS on a 32 bit LINUX version.

If you enter file /home/gams/gamsinst, the output will tell you that this is the 64 bit version of GAMS:

gamsinst: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), for GNU/Linux 2.4.0, statically linked, not stripped

while the 32 bit version returns:

gamsinst: ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), for GNU/Linux 2.2.5, 
dynamically linked (uses shared libs), not stripped

Solution: Install the 32-bit version of GAMS (or upgrade your operating system to a 64 bit version). The command uname -a will tell you more information about your version of UNIX. Hint: On most systems the command top will provide more information about the number of CPU's, the available memory, and the system load.