14th September 2021 at 11:01 am #13384
I have had a look at that page on your site.
I have also found the same issue exists on the page Administration > Site administration > Logs.
There is nothing particularly special about these two pages compared to all the other admin and front-end pages, apart from their names. So my best guess is that your server, and only specific to the A-D domain, has a server-based security setting (by your host) that traps and rejects the name of that page. We have seen similar issues on a few sites before with the “Users” admin page. The only solution is for the web host to remove that restriction.
It is possible there is more information available on your server error logs though, which might help.
The only other issue I can see, although I do not know why it would matter in this case, is that your sites are not set to use https (SSL/secure access). These days every web browser will complain about that, and make life generally difficult for you and your site visitors. I strongly recommend you change that when you can.Nigel
My personal kiwitrees site is www.our-families.info