I not sure I should revive this thread or create my own, but here goes:

I have the somewhat the same problem as described above: When users register, I no longer get a message. I use Private registration, so this is very annoying.

I recently upgraded my DNN portals from 4.x to 5.2.3. This feature worked before, but now it's broken. I realize that the whole user registration module has changed from one version to the other, but I cannot find any smelly stuff in the code. This is what I've tried so far:

1. Register new user - tried all methods (Private, Public, Verified). All send a mail to the user himself, but not to the admin. I've tried changing the admin.
2. Host SMTP Mail Test - this works just fine
3. Newsletter (send to admin) - (this works just fine)
4. Look through to Mail and UserModuleBase code to see if there were anything interesting - nothing so far
5. Change language settings, register on different portals with different languages and different admins with different preferred locales.
6. I asked my provider to check the SMTP server to see if there was anything stuck there, but haven't heard from him yet... I just don't think that this is the problem...
7. Checked the event viewer - no logs or errors so far, but I get TWO messages saying that the user has been created...

The weird thing is, that at first I did not get any mails to the newly registered user. This problem was magically solved by editing the language settings (I use danish language for some portals). I removed a portal specific GlobalResources.da-DK.Host.resx where the EMAIL_USER_REGISTRATION_PRIVATE_BODY was not present.

Does anyone have any idea what could be going on here?