Lost Admin access after Upgrade to Version 20

christofwenz

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Hi everyone,

I'm dealing with a situation where I've been handed a 3CX system without any documentation or credentials, and I'm hoping someone can point me in the right direction.

Here's the situation:

- The system was running 3CX v18 on-premise (Linux/Debian) and had to be upgraded to v20 because the license was about to expire.
- After the upgrade to v20, I have no way to log in to the management console.
- The old admin account from v18 no longer exists in v20.
- The system is running behind a Fritz!Box router and is only reachable via its local IP address — the FQDN (*.my3cx.de) does not resolve.
- I attempted a password reset via login.3cx.com using the registered email address, but no reset email was received.
- The previous reseller has already been removed from the admin panel on login.3cx.com.
- I have no SSH access to the server and no root/user credentials for the underlying Linux system.
- I do have a full backup from v18 (taken before the upgrade). In this backup I can see that one extension (DN 00) has the system_owners role assigned. I also have the license key, registered email, company name, and FQDN from the backup.

What I've already tried:
- Password reset via login.3cx.com → no email received
- Logging in with the old v18 admin credentials → not accepted

My questions:
1. Is there a way to regain access to the management console without SSH access to the server?
2. Can I somehow re-link the on-premise installation to a new or existing 3CX account?
3. Has anyone been in a similar situation after a v18 → v20 upgrade and found a solution?
4. If the only option is to contact 3CX support directly — what is the best way to reach them with proof of ownership?

Any help or pointers would be greatly appreciated. Thanks in advance!
 
Hello christofwenz,

This is not good !
You can try to contact 3CX with this link:
https://www.3cx.com/contact/

Not sure if they can help you.
You have no backup anywhere, not even on an old laptop somewhere?

Paulo
 
I have a backup from version 18 before the upgrading to version 20.
 
Hello @christofwenz,

In V20 installations, the Admin Root credentials from V18 are not available.
See also our blog V20 Upgrade Checklist & FAQ
One of the reasons you might not be getting the password reset is if the email configured on the System Owner extension is used in multiple extensions. Since you have an available backup, you can check this.
Keep in mind that since you do not have SSH access, you will have to reinstall the machine.
If this is not the case, though, it is advised to open a ticket to the technical support team to further check this.
 
The mail-adress is used in this extension and for the license-Owner.
Could this be a problem?
 
No, it could only be a problem if it is used with multiple extensions.
We would suggest checking the Junk/Spam folder of the mailbox and the SMTP server on your side to ensure that it does not block the emails from being delivered from [email protected].
 
The system is running behind a Fritz!Box router and is only reachable via its local IP address — the FQDN (*.my3cx.de) does not resolve.
Could this be the case why no mails are coming?
 
Can i test it somehow, if 3cx can send mails?
 
> Password reset via login.3cx.com

FWIW this site is not related to credentials for your server.

You would log in as the 00 user. Can you reset that password from your login page? Hopefully it’s a unique email on your server…?

> Could this be the case why no mails are coming?

It seems a decent guess the FQDN/license were inactive because the server was on such an old version…AFAIK that would stop 3CX SMTP from working, assuming the server was not using custom SMTP.
 
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