If you do an M-x man keyword search with nothing matching, like M-x man -k jkjkjkjk Ret The result shown is error in process sentinel: Can't find the -k jkjkjkjk manpage where reads as if it thought the "-k" was the page name -- which is not the case, M-x man understands -k is an "apropos" keyword search. This could be due to "man-db" (as used in debian and elsewhere) printing nothing for no matches, as opposed to a "nothing appropriate" message which Man-bgproc-sentinel knows to look for. Perhaps something along the lines below, 2009-12-07 Kevin Ryde * man.el (Man-bgproc-sentinel): When "-k foo" produces no output show error "no matches" rather than "Can't find manpage", as the latter reads like -k was interpreted as a page name (which is not so).