I've wasted invested some time into investigation so I can share my suspisions - I believe problem is related to the switch from carbonio-admin-ui to carbonio-admin-console-ui that happened somewhere between 25.6.0 and 25.12.0. Ubuntu package system handles the package conflicts pretty well and allows to only one of those to be installed, HOWEVER:
   the fact that problem can be relieved by switching the entire admin/ contents with the ones from older Carbonio installation makes me believe that it is the contents of /opt/zextras/admin/iris/components.json that are incorrectly migrated to serve carbonio-admin-console-ui and a migration procedure to adjust the contents of this file to match the installed packages should be provided.

apt update
apt upgrade -y
apt install carbonio-ce -y
pending-setups -a
su - zextras
zmcontrol restart

sudo systemctl list-units carbonio*
chown zextras:zextras /opt/zextras/data/tmp/nginx/client
apt install carbonio-catalog
pending-setups -a
systemctl restart carbonio-directory-server.target
systemctl restart carbonio-appserver.target
systemctl restart carbonio-proxy.target
systemctl restart carbonio-mta.target
Reboot

I see they have you downgraded in this forum!

My question to you: what is it that you need from Carbonio CE that Maldua Zimbra does not?

Zimbra for one does work without any hassle.

I have given up on Carbonio CE as it is not worth my time.

This is not helping neither of us.

Talking like this is pointless. I have read all the posts again and again. And I did the installation countless times. I asked again and again that when you do not get the page try to inspect the browser page using Developers Tools. It would give you some useful insights. 

But as I said it is pointless now. 

Good Luck.

I would be really happy to help and other users on this. 

I have installed Carbonio CE 25.12.0 many times so far on Ubuntu 24.04LTS. And as I said on another post that carbonio-catalog.service is responsible for the login page. After restarting this service or the server everything works normally. And after a fresh installation, when you get "Something went wrong... " if you inspect the browser page you would find that it is related to catalog. 

I would be very happy to help you on this. And I can assure you that it is not a service blocker. 

Let me know if you have any idea on how can we sort this out.

Thanks

@jim1985 

Hi!

I'm sorry, I really missed the Red Hat issue.

That's why I asked @Sharif him to look at the whole post because there's a lot of information there. I believe he's seen it from the beginning (I want to believe that, but...). Anyway, unfortunately, the forum is increasingly demonstrating Carbonio's support problems (I know I use the free version), but even so, months of problems is very frustrating....

Hey

I too am using the free version, I don’t mind the reduced support that comes with the free community model, but this is clearly a bug in their software somewhere that likely only Carbonio are going to be able to fix.

In my opinion this problem was introduced in the 25.9 release as I wasn’t getting the problems logging in to the Webmail or the Admin panel on any of the releases prior to 25.9

As I have mentioned previously, if I copy the “admin & “web” folders from a 25.6 installation over to an upgraded 25.12 installation, it fixes the problem. But this really isn’t ideal & certainly isn’t a recommended solution, but for the time being it does work.

Does this give Carbonio / Zextras any clue towards fixing the problem I wonder? Or to put it another way, can they offer an explanation to why this gets things working again?