Date: 2019-06-26 08:31:03
ID: -5
Error occured in: Global
Count: ∞
Message: ..\AddOns\MailNotifier\MailNotifier.lua line 179:
PlaySoundFile Error - Invalid fileDataID for sound.
Debug:
[C]: ?
[C]: PlaySoundFile()
MailNotifier\MailNotifier.lua:179: AddNewMail()
MailNotifier\MailNotifier.lua:100:
MailNotifier\MailNotifier.lua:84

yeah there seem to be some issues on classic as well,

I looked at the code and it checks for a boolean (but I have no idea where that is set) and also the audio file does not exist in my install folder

https://github.com/Jaliborc/MailNotifier/blob/master/MailNotifier.lua#L178-L180

in my local file I changed this:

if not MailNotifier_DisableSound then
	PlaySoundFile('Interface\\AddOns\\MailNotifier\\NewMail.mp3')
end

to this:

PlaySoundFile('Sound/Spells/LevelUp.ogg', 'Master')

and it works like a charm

edit:

apparently "not MailNotifier_DisableSound" returns true because it's never set to false, so the only issue with the current code is that the file doesn't exist.

you need to put a file in WOW/Interface/Addons/MailNotifier/NewMail.mp3 (I would assume, I didn't try)