So, if you are trying to upload a file to the said website (YouTube) and it is in MP4 format but the codec for the video or audio is not suitable for the accepted one then it will cause such troubles of unsuccessful or no uploading, at all.
Kwa hivyo, ikiwa unajaribu kupakia faili kwenye tovuti iliyotajwa (YouTube) na iko katika umbizo la MP4 lakini kodeki ya video au sauti haifai kwa ile iliyokubaliwa basi itasababisha matatizo kama haya ya kutofaulu au kutopakia, hata kidogo.