Have a look at the registration email that is in your lang settings:

admin/languages

Search for your domain... see what you find.

Thanks fbkca. I will have a look...

Hello fbkca. I had a look. The only directory I could see that is close to your description is:

/ow_pluginfiles/admin/languages

In there there are three sub-directories:

/export

/import

/tmp

These only contain empty index.html files.

So, I'm unable to find it.

uhhh try your admin panel...

http://www.mywebsite.com/admin/languages

Okay I see. At the /admin/languages in the Admin I can see how to edit messages. But there are messages that use $site_url to add the site's URL. My problem is that $site_url adds the url for my old site. I have since migrated the site to a new server with a different domain name. I have set the new domain name in the config.php and also updated all references to the old domain name in the database. But, $site_url still contains the old domain name.

I need to know how to update $site_url.

The 'Email Verification' email has the correct links to the new site / domain. But, the 'Domain.tld registration' email - sent out after the new user has verified their email and been approved by admin - still has the links from the old site / domain.

Hope this provides a clue as to what could be the cause :-)

One further snippet of information. If I send out an 'Invitation to Domain.tld' email, I get the following:

Hi, We invite you to join our website - new_domain.tld. Please join here: http://new_domain.tld/join?code=XXXXXXXXXXX Administrationhttp://old_domain.tld/

So, the link at 'Please join here:' is correctly showing the new domain.But, the link at the bottom signature is still showing the old domain.

and when you search for old_domain.tld in admin/languages nothing shows up? Search all sections. The email templates have both headers and footers. I suspect that one of your footers ones has the domain entered into it instead of $site_url 

It's crazy. I searched All Sections for the old_domain.tld and the new_domain.tld, but found nothing.

strange. I'm out of ideas... The only place that variable is read from is the config...

clear your cache?

Justin, answering your PM to me.

Links in invitation and verification emails are working correctly because they use different variable: {$url}

As I understand right now all emails where {$site_url} variable is used are pointing at your old domain name.

{site_url] is pulled from config.php. So changing it there should have been enough.
BUT, if notifications are old ( meaning that they were generated when old URL was in config.php), they will be  linked to old domain name.  Since once notification is generated it becomes a static content.
 
Have you tried testing with new notifications?

- provide screen shot of your config.php settings ( or send it as text)
- provide screen shot of the email with incorrect URL. Point our which links goes to wrong URL ( would be great if you can send this as text as well).
- if possible provide your new site URL .
- on your join page, do you have Terms of Use checkbox? Where does the link in terms of use lead? Old domain name or new one?

Aliia, I will send you the text files soon.

On the join page, the Terms of Use links to the correct page. I did have an issue with that at first, when it was going to the old url, but solved it by re-installing the Facebook Connect plugin (it's link had become deactivated, i.e. clicking it did nothing). I have since had other issues with this plugin, so it is now uninstalled. Don't know if this could be related to the email link issues I am having.
Thanks.

Justin, 

Has the issue been resolved or not?

Will get back to this in a couple of days. Thank you.

Ok, take your time. 

Hello Aliia,

Are you having a further look at this issue?

If these links are hard-coded somewhere, can you let me know where they are hard-coded so that I can change them myself?

Thank you!

This issue is still open and I'm getting no reply from Oxwall.

Justin, please PM me the following: 

screen shot of your config.php settings ( or send it as text)
screen shot of the email with incorrect URL. Point our which links goes to wrong URL ( would be great if you can send this as text as well). 
possible provide your new site URL .
on your join page, do you have Terms of Use checkbox? Where does the link in terms of use lead? Old domain name or new one?

Hi Ross,

I did all of this with Aliia, but she has somewhat left me hanging in the air. I will PM you the email exchange with Aliia. Thanks!