Hello,
There was POM 3.1.1. Agent API worked correctly.
POM was upgraded to 3.1.3.2.5 according to Flash issue.
Agent API and url were upgraded as well.
But when Agent is trying to login to POM then he gets error 9012 - please wait while system is initializing
Nothing changed was in config. Just POM was upgraded.
SampleJava client has the same issue.
Does somebody familiar with this issue?
Rg, Dmitry

Some things to check:
Certificates - You may need to re-exchange the certs (AEP/POM/Application runtimeconfig)
POM Application Entries - Verify that the POM applications are good and using the correct ports
Check server.xml - Check the settings in the tomcat server.xml
Avaya KB - Check the Avaya KB Doc ID: SOLN315394, it seems like a similar issue to yours

Thank you very much.
Your advice helped. Looks like during upgrade installed added wrong string to config file of app server. According to this App server used wrong certificates.
Rg, Dmitry