TuxCare Extended Lifecycle Support for PHP can't be enabled in Plesk: CLN response (HTTP 400): You can not register a new server! Right now you have 1 server and your license limit is 1.

Symptoms

• Attempt to enable TuxCare Extended Lifecycle Support for PHP extension result in errors like below:

PLESK_INFO: CLN response (HTTP 400): You can not register a new server! Right now you have 1 server and your license limit is 1.

• Attempts to enable via CLI result in similar errors:

# plesk ext tuxcare-els --enable
Execution installer has failed with exit code 1, stdout: Got incorrect status from CLN: HTTP/1.1 400 Bad Request
...
{"message":"Smth went wrong","details":"(#_#) You can not register a new server! Right now you have 1 servers and your license limit is 1."}
...
ERROR: Failed to configure TuxCare ELS repositories
exit status 3

or

# plesk ext tuxcare-els --enable
...
Error (No token was returned from CLN)” / “ERROR: Failed to install TuxCare ELS PHP repositories

Cause

Issue could trigger for the following reasons:

• Bug in TuxCare Extended Lifecycle Support for PHP extension: installer registered the server in CLN before the rest of the setup steps. If a later setup step failed, the registration wasn't released, so errors are provided on re-run.

or

• Another license is already bound to an IP address.

Resolution

1. Log into Plesk
2. Navigate to Extensions > Updates menu and update TuxCare Extended Lifecycle Support for PHP to version 1.3.2-19305 or newer (or reinstall the extension).

If the error still triggers, create a ticket for technical support.