* the error message in the error file (w4d_interface.err). This file is in your current working directory.

* the most recent commands file in the temporary directory. If the environment variable ENVIS_W4D_KEEP is not defined, you will need to define it and re-run the option with the same details to re-produce the error which can then be examined.

* the error message in the error file (w4d_interface.err). This file is in your current working directory.

* the commands file as per running a Vulcan program.

* the output in the shell window and find the first prompt that is repeated. The repeated prompt is the point at which the program failed. Hence, you must modify the corresponding Whittle interface input to an entry acceptable by the particular Whittle program.

* the log file (if you created one).