> > The games work great, but I'm getting this error message when launching a game (not
> > every game, but many..)
> it just means, that particular machine's ROM or CD-ROM or DVD-ROM or GD-ROM or HDD or
> FDD needs to be redumped. it's not a problem on your side.
yeah, this is one of the more annoying (and pointless) warning messages, as it really doesn't tell you anything that the other flags don't (if a game actually has a bad gfx rom it will be flagged as imperfect gfx)
it usually flags up on missing NO_DUMPs which aren't even used by the emulation, eg gals and pals.
I think it should be disabled except in the case of actual CRC errors during the loading myself, where there is something unexpected / wrong with the roms you're using vs. the ones MAME expects.