Users are unable to activate the sites they sign-up for

Have you tried turning off all your plugins?

Yes Already tried.

The only reason I could figure out is that the activation e-mail contains the the subdomain link eg https://www.subsite.mainsite.com/wp-activate.php/XXXXXX
instead of the main site link eg https://www.subsite.mainsite.com/wp-activate.php/XXXXXX

When I remove the subsite name from that link and try without that, I am able to activate that site…

Any suggestions on how to check why the activation email contains the subsite link

Cheers
PC

You didn’t mess around and change your main site ID did you? (those two links are the same, I’m assuming the second was meant to be https://www.mainsite.com/wp-activate…. )

Yeah, you are right, the second was meant to be https://www.mainsite.com/wp-activate…

and how would I check whether what my mainsite Id is. I do not remember making any changes like that.

And just to do some R&D, I removed the subsite name from the link, that way I was able to activate the subsite, but after that the password being sent to me, is not working.

Please advise

Cheers
PC

No plugins… nothing in mu-plugins?

Nups,

Disabled all of them. No redirect plugis as well.. So right now, no plugins at all.

Added the below in wp-config.php as advised in the multisite setup

define( 'MULTISITE', true );
define( 'SUBDOMAIN_INSTALL', true );
$base = '/';
define( 'DOMAIN_CURRENT_SITE', 'xxxxx.com' );
define( 'PATH_CURRENT_SITE', '/' );
define( 'SITE_ID_CURRENT_SITE', 1 );
define( 'BLOG_ID_CURRENT_SITE', 1 );

That makes no sense at all. Did it EVER work?

No for this install it never worked, however for my other multisite installs, they are working fine. and I made no mistakes while I installed these networks. Same steps and settings were followed

You don’t have any extra, complex, redirects in your .htaccess?

Nothing apart from the below

RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]

# uploaded files
RewriteRule ^files/(.+) wp-includes/ms-files.php?file=$1 [L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule . index.php [L]