Lastest RetroPie 4.1 not able to launch any mame4all roms.. ERROR: required files are missing

[WilsonB]

UPDATE: A few minutes later I tried a rom from a different batch and that worked... So it was bad corrupt Rom

Lastest RetroPie 4.1 on Pi 3 not able to launch any mame4all roms that worked before.
RetroPie boots up, had problems config. PS3 joystick until after updating that section. Once able manuver in menu, added mame rom to RetroPie/roms/mame-mame4all/ folder - restart..
See games as options in MAME section, select it and it tries to start.. then
"ERROR: required files are missing, the game cannot be run"

Did a reimage 2nd time and still had to do some updates because the PS3 joystick wouldn't recognize after installing drivers. Not sure if this is whats breaking it or if it's broke in downloaded image.

[batesman]

First, let me ask you this...How much of the documentation have you read here that relates to the setup of MAME and its roms? There is a common cause for 99.9% of the times this error is seen and its well documented here.

Second, when you say "roms that worked before"....Before what?

[rbaker]

@WilsonB Yeah, it's a bad post, makes you look seriously lazy. You need to read the guide. MAME roms are not universal. More importantly though https://retropie.org.uk/forum/topic/3/read-this-first. Angry with my response? don't be. Be angry with yourself. People on this forum spend countless hours repeating the same old thing over and over and over and over and over and over because people do not read the guide. For example, I wrote this. I spent time doing it to prevent this question. It complements the full guide. Have you read it? Have you read this? I say No. No. No. No. No you have not.