https://community.intel.com/t5/Intel-Fortran-Compiler/How-can-I-change-the-source-form-in-Intel-Fortran-compiler-9-0/m-p/774082#M24099 You probably have the file named with a .f90 file type. The easiest thing to do is to rename it with a .f or .for file type, which implies fixed-form. Otherwise you can add /fixed to the command line. Wed, 05 Apr 2006 21:44:21 GMT Steven_L_Intel1 2006-04-05T21:44:21Z https://community.intel.com/t5/Intel-Fortran-Compiler/How-can-I-change-the-source-form-in-Intel-Fortran-compiler-9-0/m-p/774081#M24098 I am trying to compile fortran code which has "C" for a comment line using Intel fortran compiler for Windows 9.0. When I try to compile this code, I am getting an error saying "unknown variable". I found from Intel Fortran language manual that there are actually two source forms. I guess free source form is the default. But I think fixed source form suports the comment line starting with "C". My question is how can I change the option of free source form to fixed source form? I am using command line to compile the fortran program. Any suggestion with regard to this is really appreciated.<BR /><BR />Thanks,<BR />Lalitha Wed, 05 Apr 2006 21:02:24 GMT https://community.intel.com/t5/Intel-Fortran-Compiler/How-can-I-change-the-source-form-in-Intel-Fortran-compiler-9-0/m-p/774081#M24098 sv6wc 2006-04-05T21:02:24Z https://community.intel.com/t5/Intel-Fortran-Compiler/How-can-I-change-the-source-form-in-Intel-Fortran-compiler-9-0/m-p/774082#M24099 You probably have the file named with a .f90 file type. The easiest thing to do is to rename it with a .f or .for file type, which implies fixed-form. Otherwise you can add /fixed to the command line. Wed, 05 Apr 2006 21:44:21 GMT https://community.intel.com/t5/Intel-Fortran-Compiler/How-can-I-change-the-source-form-in-Intel-Fortran-compiler-9-0/m-p/774082#M24099 Steven_L_Intel1 2006-04-05T21:44:21Z