In case of error during the execution of HSPF, look at the contents of the status window. More detailed messages may be found by clicking the Output button in the status window.
Also be sure to check for run interpreter error messages, which would be written to the HSPF echo file. For a project created with WinHSPF, the echo file should be in the same folder as the UCI file. The echo file name will consist of the base name of the project followed by a ‘.ech’ extension.