The file you sent me was not internally an rtf file. It did have an rtf suffix but if you examine the contents using a tool that shows you the binary contents of the file you will see that it is not an rtf file. It looks like a doc or a docx file and consequently your test worked. My program works if you start with a file that has doc or docx format internally and try to save it as a doc file. The problem is that if you open a real rtf file and then try to save it as a doc file you cannot suppress the Save dialog.

It appears that you are confused about internal formats and the suffix that a file has. A file with a suffix of rtf does not mean that the internal contents are rtf.