It didn't even get a theatrical release! It was supposed to but it went right to video due to the fact Warner Brothers decided they didn't want it.
Oh yeah, my bad, I got my facts mixed up. ><
Ironically, that was kind of a similar case with <i>The Brave Little Toaster</i> (which like <i>Rover Dangerfield</i>, was a Hyperion film): Disney originally had the rights to the movie, but they didn't think it would be a success for them, so they dropped out of the project, afterwards, Hyperion went ahead and made it as a Sundance-esque independent film, and then once they saw how big a hit it turned out to be after all, Disney bought back the rights again so they could distribute it on home video and such.
And don't even get me started on the confusion of it's two direct-to-video sequels... "Goes to Mars" was released in 1998, and "To the Rescue" was released in 1999, however, the events of "To the Rescue" (Rob and Kris being in college and dating) took place before "Goes to Mars" (Rob and Kris being married and having a baby, while Rob now has his own veterinary practice)... as it turns out, "To the Rescue" WAS released before "Goes to Mars", in 1997 to be exact... in all other countries BUT the U.S., where for some reason, it's release was delayed two years, and didn't come out until "Goes to Mars" was already released in 1998.