I have two sites on the same server, on different directory and with different third level url.
They are configured to user Intertiki to centralize user accounts.
After upgrading both from 9.6 to 9.9 and then to 12.3, login on the slave no longer works.
I get this error:
XMLRPC Error: 2 - Invalid return payload: enable debugging to examine incoming payload
How can I find more help?