Hello, I have Ubuntu 10.04 and used the latest Intel Fortran compiler (student version) to make a shared library 'swat2009_i64_calibrate.so'. I encounter no error or warning when applying the dyn.load function like this: dyn.load('swat2009_i64_calibrate.so') However, the is.loaded function yields false: is.loaded('swat2009_i64_calibrate.so') FALSE I tried slight variations, based on postings, such as is.loaded('swat2009_i64_calibrate_'), but never get TRUE. p. 71 of "Writing R Extensions" makes me suspect that using the file.path function might somehow help, but the function documentation is too brief to bring me clarity. This shared library has been successfully used with dyn.load by a colleague having CentOS, after being compiled with the same Makefile with an Intel Fortran compiler. I compiled it on mine using the same Makefile with no warnings or errors. How can I get is.loaded to wring TRUE? I am a newbie. Any help would be much appreciated. John Joseph [[alternative HTML version deleted]]