c:/ws/fpfdev/depot/QA/EDG/EDG_priv/FPF_Dev.br/src $ hp2ps -c
bin\hp2ps.exe: Disaster! (bucket out of range)
...then the chances are it's because you have a partially truncated .hp file (eg if your program didn't exit cleanly). This is easily fixed, by searching for the last BEGIN_SAMPLE line in the file, and deleting everything from there onwards.