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V445 Puppis is the only known example of a helium nova, where a layer of helium-rich gas accretes onto the surface of a white dwarf in a cataclysmic variable, with runaway helium burning making for the nova event. Speculatively, helium nova can provide one path to produce a Type Ia supernova (SNIa), within the larger framework of single-degenerate models. Relatively little has been known about V445 Pup, with this work reporting the discovery of the orbital period near 1.87 days. The companion star is 2.65\(\pm\)0.35 R\(_{\odot}\) in radius as an evolved giant star stripped of its outer hydrogen envelope. The orbital period immediately before the 2000 eruption was \(P_{\rm pre}\)=1.871843\(\pm\)0.000014 days, with a steady period change of (-0.17\(\pm\)0.06)\(\times\)10\(^{-8}\) from 1896--1995. The period immediately after the nova eruption was \(P_{\rm post}\)=1.873593\(\pm\)0.000034 days, with a \(\dot{P}\) of (\(-\)4.7\(\pm\)0.5)\(\times\)10\(^{-8}\). The fractional orbital period change (\(\Delta P/P\)) is \(+\)935\(\pm\)27 ppm. This restricts the mass of the gases ejected in the nova eruption to be \(\gg\)0.001M\(_{\odot}\), and much greater than the mass accreted to trigger the nova. So the white dwarf is losing mass over each eruption cycle, and will not become a SNIa. Further, for V445 Pup and helium novae in general, I collect observations from 136 normal SNIa, for which any giant or sub-giant companion star would have been detected, yet zero companions are found. This is an independent proof that V445 Pup and helium novae are not SNIa progenitors.