Is there a way to restore default key mappings in MAME?

[TxGlenn]

Is there a way to restore default key mappings in MAME without reinstalling/recompiling?

[NickG]

delete your configs. 

[TxGlenn]

thanks nick

[fjl]

Deleting the configs is kind of drastic.

If you just want to restore certain functions/buttons then go into the input control menus within mame. The ones that have been changed will usually be yellow in color. The ones in white will be the default settings. To set the yellow ones back to default try changing them but press Escape to delete the entry. Do this twice and on the second attempt it it will go back to default.

[u_rebelscum]

Or edit the file(s) with a text or xml editor.

Which of the three ways to go depends what's "broken" and what was changed that you want to have after.  If "UI Configure" (aka "the tab button") was changed to none, that rules out editing in game.  If you have a lot of changes you want to keep, or only want to change one back to default, deleting the config files is not the easiest way.  If you want everything back to default, deleting is the easiest.

Having choices is great, except for people looking for the one answer.